criyle/codenet-compile-errors huggingface dataset:
Language: C++

#include<bits/stdc++.h>
#include<queue>
using namespace std;
int main () {
  int N;
  cin >> N;
  vector<vector<int>>son(N + 1, vector<int>(N + 1));
  vector<int>si(N + 1, 0);
  for (int i = 2; i <= N; i ++) {
    int a;
    cin >> a;
    son[a][si[a]] = i;
    si[a] ++;
  }
  vector<int>X(N + 1);
  for (int i = 1; i <= N; i ++) cin >> X[i];
  vector<int>per;
  queue<int>que;
  que.push(1);
  per.push_back(1);
  while(!que.empty()) {
    int u = que.front();
    for (int i = 0; i < si[u]; i ++) {
      int ne = son[u][i];
      per.push_back(ne);
      que.push(ne);
    }
    que.pop();
  }
  dp[1010];
  for (int i = N - 1; i >= 0; i --) {
    int nw = per[i];
    if (!si[nw]) dp[nw] = X[nw];
    else {
      vector<int>dp_(5050, 1e9);
      dp_[0] = 0;
      for (int i_ = 0; i_ < si[nw]; i_ ++) {
        int so = son[nw][i_];
        for (int j = X[nw]; j >= 0; j --) {
          if (j + X[so] <= X[nw]) {
            if (dp_[j + X[so]] > dp_[j] + dp[so]) {
              dp_[j + X[so]] = dp_[j] + dp[so];
            }
          }
          if (j + dp[so] <= X[nw]) {
            if (dp_[j + dp[so]] > dp_[j] + X[so]) {
              dp_[j + dp[so]] = dp_[j] + X[so];
            }
          }
        }
      }
      dp[nw] = 1e9;
      for (int i_ = 0; i_ <= X[nw]; i_ ++) {
        if (dp[nw] > dp_[i_]) dp[nw] = dp_[i_];
      }
      if (dp[nw] == 1e9) {
        cout << "IMPOSSIBLE" << endl;
        return 0;
      }
    }
  }
  cout << "POSSIBLE" << endl;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:30:3: error: 'dp' was not declared in this scope; did you mean 'dup'?
   30 |   dp[1010];
      |   ^~
      |   dup
Language: C++

#include<bits/stdc++.h>
#include<queue>
using namespace std;
int main () {
  int son[1001][1001];
  int N;
  cin >> N;
  vector<int>si(N, 0);
  vector<int>par(N);
  for (int i = 1; i < N; i ++) {
    cin >> par[i];
    son[i][si[i]] = -- par[i];
    si[i] ++;
  }
  queue<int>tre;
  vector<bool>vis(N, false);
  vector<int>far(N, -1);
  far[0] = 0;
  tre.push(0);
  int fli[1010][1010];
  vector<int>fl_s(N, 0);
  fli[0][fl_s[0]] = 0;
  fl_s[0] ++;
  int ma = 0;
  while(!tre.empty()) {
    int k = tre.front();
    for (int i = 0; i < si[k]; i ++) {
      tre.push(son[k][i]);
      far[son[k][i]] = far[k] + 1;
      if (ma < far[k] + 1) ma = far[k] + 1;
      fli[far[k] + 1][fl_s[far[k] + 1]] = son[k][i];
      fl_s[far[k] + 1] ++;
    }
    tre.pop();
  }
  vector<int>X(N);
  for (int i = 0; i < N; i ++) cin >> X[i];
  dp[1010];
  for (int i = 0; i < N; i ++) {
    dp[i] = -1;
  }
  for (int i = ma; i >= 0; i --) {
    for (int j = 0; j < fl_s[i]; j ++) {
      if (i == ma) {
        dp[i] = 0;
        continue;
      }
      int j_ = fli[i][j];
      vector<vector<int>>dp_(si[j_] + 1, vector<int>(5050, 1e9));
      dp_[0][0] = 0;
      for (int k = 0; k < si[j_]; k ++) {
        for (int l = 0; l <= X[j_]; l ++) {
          int al = son[j_][k];
          if (l + X[al] <= X[j_]) {
            if (dp_[k + 1][l + X[al]] > dp_[k][l] + dp[al]) {
              dp_[k + 1][l + X[al]] = dp_[k][l] + dp[al];
            }
          }
          if (l + dp[al] <= X[j_]) {
            if (dp_[k + 1][l + dp[al]] > dp_[k][l] + X[al]) {
              dp_[k + 1][l + dp[al]] = dp_[k][l] + X[al];
            }
          }
        }
      }
      for (int k = 0; k <= X[j_]; k ++) {
        if (dp_[si[j_]][k] == 1e9) continue;
        if (dp[j_] == -1 || dp_[si[j_]][k] < dp[j_]) {
          dp[j_] = dp_[si[j_]][k];
        }
      }
      if (dp[j_] == -1) {
        cout << "INPOSSIBLE" << endl;
        return 0;
      }
    }
  }
  cout << "POSSIBLE" << endl;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:38:3: error: 'dp' was not declared in this scope; did you mean 'dup'?
   38 |   dp[1010];
      |   ^~
      |   dup
Language: C++

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef vector <int> vi;
#define f first
#define s second
#define FOR(i,s,e) for (ll i = s; i <= (ll)e; i++)
#define DEC(i,s,e) for (ll i = s; i >= e; i--)
#define aFOR(i,s) for (auto i: s)
#define maxn 1000
#define maxx 500
#define INF 1e9
#define pb push_back
#define int ll
int N;
int p[maxn];
int A[maxn];

vi adj[maxn];

int dp[maxn];

int dp2[maxn][maxx];
int B[maxn];

bool np = 0;
void dfs(int x){
	if (vis[x] || np){
		np = 1;
		return;
	}
	vis[x] = 1;
	

	dp[x] = INF;
	aFOR(i,adj[x]){
		dfs(i);
	}
	int sm = 0;
	FOR(i,0,adj[x].size()-1){
		B[i] = abs(A[adj[x][i]] - dp[adj[x][i]]);
		sm += min(A[adj[x][i]],dp[adj[x][i]]);
	}
	if (A[x] < sm){
		dp[x] = INF;
		return;
	}
	FOR(i,0,adj[x].size() - 1){
		FOR(j,0,A[x] - sm){
			dp2[i][j] = INF;
			if (i == 0){
				dp2[i][j] = B[i];
				if (j >= B[i]) dp2[i][j]  = 0;
			}else{
				if (j >= B[i]) dp2[i][j] = min(dp2[i-1][j] + B[i],dp2[i-1][j-B[i]]);
				else dp2[i][j] = dp2[i-1][j] + B[i];
			}
		}
	}
	
	if (adj[x].empty()) dp[x] = 0;
	else dp[x] = dp2[adj[x].size()-1][A[x]-sm] + sm;
}

int32_t main(){
	cin>>N;
	
	FOR(i,2,N){
		cin>>p[i];
		adj[p[i]].pb(i);
	}

	FOR(i,1,N) cin>>A[i];

	dfs(1);
	
	
	if (dp[1] == INF || np) cout<<"IMPOSSIBLE";
	else cout<<"POSSIBLE";
}


Compiler output:
a.cc: In function 'void dfs(ll)':
a.cc:28:13: error: 'vis' was not declared in this scope; did you mean 'vi'?
   28 |         if (vis[x] || np){
      |             ^~~
      |             vi
a.cc:32:9: error: 'vis' was not declared in this scope; did you mean 'vi'?
   32 |         vis[x] = 1;
      |         ^~~
      |         vi
Language: C

//此程序使用了qt专属名称，请勿模仿。侵权必究！！！
//我真是太菜了啊……
#include<bits/stdc++.h>
using namespace std;
#define ll long long
const int N=1010;
int n,t=0,b[N<<1],w[N],f[N][2],g[N];
bool v[N<<1];
struct tq
{
	int y;
	int nxt;
}a[N<<1];
inline void in(int x,int y)
{
	a[++t].nxt=b[x];
	b[x]=t;
	a[t].y=y;
	return;
}
inline int read()
{
	int sum=0,flag=1;
	char c;
	for(;c<'0'||c>'9';c=getchar())
	{
		if(c=='-')
		{
			flag=-1;
		}
	}
	for(;c>='0'&&c<='9';c=getchar())
	{
		sum=(sum<<3)+(sum<<1)+c-'0';
	}
	return sum*flag;
}
inline void dfs(int x,int fa)
{
	memset(v,0,sizeof(v));
	int mx=0,mn=0,cnt=0;
	for(int i=b[x];i;i=a[i].nxt)
	{
		int y=a[i].y;
		if(y==fa)
		{
			continue;
		}
		dfs(y,x);
		mx+=f[y][0];
		mn+=f[y][1];
		g[++cnt]=f[y][0]-f[y][1];
	}
	if(mn>w[x])
	{
		puts("IMPOSSIBLE");
		exit(0);
	}
	if(mx<=w[x])
	{
		f[x][0]=w[x];
		f[x][1]=mn;
		return;
	}
	int m=mx-mn,ans=0;
	v[0]=1;
	for(int i=1;i<=cnt;++i)
	{
		for(int j=m;j>=g[i];--j)
		{
			v[j]|=v[j-g[i]];
			if(v[j])
			{
				ans=max(ans,j);
			}
		}
	}
	f[x][0]=mx-ans;
	f[x][1]=w[x];
	return;
}
int main()
{
	n=read();
	for(int i=2;i<=n;++i)
	{
		int x=read();
		in(x,i);
		in(i,x);
	}
	for(int i=1;i<=n;++i)
	{
		w[i]=read();
	}
	dfs(1,0);
	puts("POSSIBLE");
	return 0;
}

Compiler output:
main.c:3:9: fatal error: bits/stdc++.h: No such file or directory
    3 | #include<bits/stdc++.h>
      |         ^~~~~~~~~~~~~~~
compilation terminated.
Language: C++

// #define DEBUGGING
#include <bits/stdc++.h>
#define endl '\n'
#define ALL(V) (V).begin(), (V).end()
#define ALLR(V) (V).rbegin(), (V).rend()
template <typename T> using V = std::vector<T>;
template <typename T> using VV = V<V<T>>;
using ll = std::int64_t;
using ull = std::uint64_t;
using PLL = std::pair<ll, ll>;
using TLL = std::tuple<ll, ll, ll>;
template <typename T> const T& var_min(const T &t) { return t; }
template <typename T> const T& var_max(const T &t) { return t; }
template <typename T, typename... Tail> const T& var_min(const T &t, const Tail&... tail) { return std::min(t, var_min(tail...)); }
template <typename T, typename... Tail> const T& var_max(const T &t, const Tail&... tail) { return std::max(t, var_max(tail...)); }
template <typename T, typename... Tail> void chmin(T &t, const Tail&... tail) { t = var_min(t, tail...); }
template <typename T, typename... Tail> void chmax(T &t, const Tail&... tail) { t = var_max(t, tail...); }
template <typename T> const T& clamp(const T &t, const T &low, const T &high) { return std::max(low, std::min(high, t)); }
template <typename T> void chclamp(T &t, const T &low, const T &high) { return t = clamp(t, low, high); }
namespace init__ { struct InitIO { InitIO() { std::cin.tie(nullptr); std::ios_base::sync_with_stdio(false); std::cout << std::fixed << std::setprecision(30); } } init_io; }
#define mv_rec make_v(init, tail...)
template <typename T> T make_v(T init) { return init; }
template <typename T, typename... Tail> auto make_v(T init, size_t s, Tail... tail) { return V<decltype(mv_rec)>(s, mv_rec); }
#undef mv_rec
#ifdef DEBUGGING
#include "../../debug/debug.cpp"
#else
#define DEBUG(...) 0
#define DEBUG_SEPARATOR_LINE 0
#endif
using namespace std;

bool ok = true;
const size_t SIZE = 5000;
V<ll> edges[SIZE];
ll X[SIZE];

PLL dfs(ll cur) {
    bitset<SIZE + 10> bs;
    bs.set(0, 1);
    ll sum = 0;
    for(ll nxt : edges[cur]) {
        ll a, b;
        tie(a, b) = dfs(nxt);
        if(!ok) return PLL();
        sum += a + b;
        bs = (bs << a) | (bs << b);
    }
    for(ll i = SIZE; 0<= i; i--) {
        if(!bs.test(i)) continue;
        if(X[cur] < i) continue;
        return PLL(X[cur], sum - i);
    }
    ok = false;
    return PLL();
}

int main() {
    ll N;
    cin >> N;
    X.resize(N);
    edges.resize(N);
    for(ll i = 1; i < N; i++) {
        ll c = i;
        ll p;
        cin >> p;
        edges[p - 1].push_back(c);
    }
    for(ll i = 0; i < N; i++) cin >> X[i];
    dfs(0);
    if(!ok) cout << "IM";
    cout << "POSSIBLE" << endl;
    return 0;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:61:7: error: request for member 'resize' in 'X', which is of non-class type 'll [5000]' {aka 'long int [5000]'}
   61 |     X.resize(N);
      |       ^~~~~~
a.cc:62:11: error: request for member 'resize' in 'edges', which is of non-class type 'V<long int> [5000]' {aka 'std::vector<long int, std::allocator<long int> > [5000]'}
   62 |     edges.resize(N);
      |           ^~~~~~
Language: C++

/*** author: yuji9511 ***/
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<ll, ll> lpair;
const ll MOD = 1e9 + 7;
const ll INF = 1e18;
#define rep(i,m,n) for(ll i = (m); i < (n); i++)
#define rrep(i,m,n) for(ll i = (m); i >= (n); i--)
#define print(x) cout << (x) << endl;
#define print2(x,y) cout << (x) << " " << (y) << endl;
#define printa(x,n) for(ll i = 0; i < n; i++){ cout << (x[i]) << " \n"[i==n-1];};
vector<ll> tree[1010];
ll dp[1010] = {};
ll X[1010];
bool ok = true;
void dfs(ll cur, ll par){
    for(auto &e: tree[cur]){
        if(e == par) continue;
        dfs(e, cur);
    }
    if(tree[cur].size() == 0){
        dp[cur] = 0;
    }else{
        ll n = tree[cur].size();
        ll opt = INF;
        rep(bit,0,(1LL<<n)) {
            ll v1 = 0, v2 = 0;
            rep(i,0,n){
                ll c = tree[cur][i];
                if((bit>>i) & 1){
                    v1 += dp[c];
                    v2 += X[c];
                }else{
                    v2 += dp[c];
                    v1 += X[c];
                }
            }
            if(v1 <= X[cur]){
                opt = min(opt, v2);
            }
            if(v2 <= X[cur]){
                opt = min(opt, v1);
            }
        }
        if(opt == INF) ok = false;
        dp[cur] = opt;
    }
}
int main(){
	cin.tie(0);
	ios::sync_with_stdio(false);
    ll N;
    cin >> N;
    if(N > 10) return 0;
    ll P[1010];
    rep(i,0,N-1){
        cin >> P[i];
        P[i]--;
        tree[P[i]].push_back(i+1);
    })
    rep(i,0,N) cin >> X[i];
    rep(i,0,N) dp[i] = INF;
    dfs(0, -1);
    if(ok){
        print("POSSIBLE");
    }else{
        print("IMPOSSIBLE");
    }

}

Compiler output:
a.cc: In function 'int main()':
a.cc:61:6: error: expected primary-expression before ')' token
   61 |     })
      |      ^
a.cc:62:9: error: 'i' was not declared in this scope
   62 |     rep(i,0,N) cin >> X[i];
      |         ^
a.cc:8:36: note: in definition of macro 'rep'
    8 | #define rep(i,m,n) for(ll i = (m); i < (n); i++)
      |                                    ^
Language: C++

#include <iostream>
#include <cstdio>
#include <cstring>
#include <cstdlib>

#define int long long

const int MAXN = 1000;

int n, edge;
int X[MAXN | 1], fst[MAXN | 1];
int sum[MAXN | 1], dp[MAXN | 1][5001];

struct Edge {
  int to, nxt;
  Edge() : to(0), nxt(0) {}
  Edge(int a, int b) : to(b), nxt(fst[a]) {}
} e[MAXN];

inline int read() {
  register int x = 0;
  register char ch = getchar();
  while (!isdigit(ch)) ch = getchar();
  while (isdigit(ch)) {
    x = x * 10 + ch - '0';
    ch = getchar();
  }
  return x;
}

inline void addEdge(int a, int b) {
  e[++edge] =  Edge(a, b);
  fst[a] = edge;
}

void DP(int x) {
  int size = 0;
  for (int k = fst[x]; k; k = e[k].nxt) {
    int to = e[k].to;
    DP(to);
    sum[x] += sum[to];
    ++size;
  }
  memset(dp, 0, sizeof(dp));
  dp[0][0] = 1;
  for (int i = 1, k = fst[x]; k; k = e[k].nxt, ++i) {
    int to = e[k].to;
    for (int j = 0; j <= X[x]; ++j) {
      if (j >= X[to]) dp[i][j] |= dp[i - 1][j - X[to]];
      if (j >= sum[to] - X[to]) dp[i][j] |= dp[i - 1][j - sum[to] + X[to]];
    }
  }
  bool flag = false;
  for (int i = X[x]; i >= 0; --i) {
    if (dp[size][i]) {
      flag = true;
      sum[x] += X[x] - i;
      break;
    }
  }
  if (!flag) {
    puts("IMPOSSIBLE");
    exit(0);
  }
}

int main() {
  n = read();
  for (int i = 2; i <= n; ++i) addEdge(read(), i);
  for (int i = 1; i <= n; ++i) X[i] = read();
  DP(1);
  puts("POSSIBLE");
  return 0;
}


Compiler output:
a.cc: In function 'long long int read()':
a.cc:21:16: warning: ISO C++17 does not allow 'register' storage class specifier [-Wregister]
   21 |   register int x = 0;
      |                ^
a.cc:22:17: warning: ISO C++17 does not allow 'register' storage class specifier [-Wregister]
   22 |   register char ch = getchar();
      |                 ^~
At global scope:
cc1plus: error: '::main' must return 'int'
Language: C++

#include <iostream>
#include <cstdio>
#include <cstring>
#include <cstdlib>

const int MAXN = 2e3;

int n, edge;
int X[MAXN | 1], fst[MAXN | 1];
int sum[MAXN | 1], dp[MAXN | 1][6001];

struct Edge {
  int to, nxt;
  Edge() : to(0), nxt(0) {}
  Edge(int a, int b) : to(b), nxt(fst[a]) {}
} e[MAXN];

inline int read() {
  register int x = 0;
  register char ch = getchar();
  while (!isdigit(ch)) ch = getchar();
  while (isdigit(ch)) {
    x = x * 10 + ch - '0';
    ch = getchar();
  }
  return x;
}

inline void addEdge(int a, int b) {
  e[++edge] =  Edge(a, b);
  fst[a] = edge;
}

void DP(int x) {
  int size = 0;
  for (int k = fst[x], i = 1; k; k = e[k].nxt, ++i) {
    int to = e[k].to;
    DP(to);
    sum[x] += sum[to];
    ++size;
  }
  memset(dp, 0, sizeof(dp));
  dp[0][0] = 1;
  for (int k = fst[x], i = 1; k; k = e[k].nxt, ++i) {
    int to = e[k].to;
    for (int j = std::min(X[to], sum[to] - X[to]); j <= X[x]; ++j) {
      if (j >= X[to]) dp[i][j] = dp[i - 1][j - X[to]];
      if (j >= sum[to] - X[to]) dp[i][j] += dp[i - 1][j - sum[to] + X[to]];
    }
  }
  bool flag = false;
  for (int i = X[x]; i >= 0; --i) {
    if (dp[size][i]) {
      flag = true;
      sum[x] += X[x] - i; 
      break;
    }
  }
  if (!flag) {
    puts("IMPOSSIBLE");
    exit(0);
  }
}

int main() {`
  n = read();
  for (int i = 2; i <= n; ++i) addEdge(read(), i);
  for (int i = 1; i <= n; ++i) X[i] = read();
  DP(1);
  puts("IMPOSSIBLE");
  // for (int i = 1; i <= n; ++i) printf("%d ", sum[i]);
  return 0;
}


Compiler output:
a.cc:65:13: error: stray '`' in program
   65 | int main() {`
      |             ^
a.cc: In function 'int read()':
a.cc:19:16: warning: ISO C++17 does not allow 'register' storage class specifier [-Wregister]
   19 |   register int x = 0;
      |                ^
a.cc:20:17: warning: ISO C++17 does not allow 'register' storage class specifier [-Wregister]
   20 |   register char ch = getchar();
      |                 ^~
Language: C++

#include <bits/stdc++.h>
#define X first
#define Y second
#define pb emplace_back
#define FOR(i,a,b) for(int (i)=(a);i<(b);++(i))
#define EFOR(i,a,b) for(int (i)=(a);i<=(b);++(i))
#define rep(X,Y) for (int (X) = 0;(X) < (Y);++(X))
#define reps(X,S,Y) for (int (X) = S;(X) < (Y);++(X))
#define rrep(X,Y) for (int (X) = (Y)-1;(X) >=0;--(X))
#define rreps(X,S,Y) for (int (X) = (Y)-1;(X) >= (S);--(X))
#define all(X) (X).begin(),(X).end()
#define rall(X) (X).rbegin(),(X).rend()
#define eb emplace_back
#define UNIQUE(X) (X).erase(unique(all(X)),(X).end())

using namespace std;
typedef long long ll;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef ll LL;
typedef pii PII;
typedef pll PLL;
template<class T> using vv=vector<vector<T>>;
template<class T> inline bool MX(T &l,const T &r){return l<r?l=r,1:0;}
template<class T> inline bool MN(T &l,const T &r){return l>r?l=r,1:0;}
const ll MOD=1e9+7;

const int INF = 0x3fffffff;

int N;
vector<int> es[114514];
int X[114514];
int W[114514];

int dfs(int v) {
  int M = es[v].size();
  vector<int> dp[2];
  rep(i, 2) dp[i].resize(5001);

  int src = 0;
  int dst = 1;
  dp[src][0] = 0;

  int mins = 0;
  for (int u : es[v]) {
    int w = dfs(u);
    mins += min(w, X[u]);

    fill(all(dp[dst]), INF);
    rep(i, 5001) {
      if (i+w < 5001) dp[dst][i+w] = min(dp[dst][i+w], dp[src][i]+X[u]);
      if (i+X[u] < 5001) dp[dst][i+X[u]] = min(dp[dst][i+X[u]], dp[src][i]+w);
    }
    swap(src, dst);
  }

  if (v == 0) {
    if (mins > X[0]) {
      puts("IMPOSSIBLE");
      exit(0);
    } else return;
  }

  rep(i, 5001) {
    if (dp[src][i] <= X[v]) return i;
  }

  puts("IMPOSSIBLE");
  exit(0);
}

int main() {
  scanf("%d", &N);
  reps(i, 1, N) {
    int p;
    scanf("%d", &p);
    --p;
    es[p].eb(i);
  }

  rep(i, N) {
    scanf("%d", &X[i]);
  }

  dfs(0);
  puts("POSSIBLE");
}


Compiler output:
a.cc: In function 'int dfs(int)':
a.cc:61:12: error: return-statement with no value, in function returning 'int' [-fpermissive]
   61 |     } else return;
      |            ^~~~~~
Language: C++

#include<bits/stdc++.h>
using namespace std;
using ll = int64_t;
using P = pair<ll, ll>;;

const ll INF = 5e15;
const P impossible = P(-1, -1);
vector<vector<ll>> edge;
vector<ll> X;

P dfs(ll now, ll pre){
    vector<P> ret;
    for(ll next : edge[now]) if(next != pre) ret.push_back(dfs(next, now));
    if(!ret.size()) return P(0, X[now]);
    vector<ll> dp(5001, INF);
    dp[0] = 0;
    for(P r : ret){
        if(r == impossible) return impossible;
        vector<ll> nextdp(5001, INF);
        for(ll i = 0; i <= 5000; i++){
            if(i + r.first > 5000) break;
            if(dp[i] == INF) continue;
            if(dp[i] != INF) nextdp[i + r.first] = min(nextdp[i + r.first], dp[i] + r.second);
            if(i + r.second <= 5000) nextdp[i + r.second] = min(nextdp[i + r.second], dp[i] + r.first);
        }
        dp = nextdp;
    }
    vector<P> tmp;
    for(ll i = 0; i <= 5000; i++){
        if(dp[i] != INF){
            if(i <= X[now] && dp[i] <= X[now]) tmp.push_back(P(min(i, dp[i]), X[now]));
            else if(i > X[now] && dp[i] > X[now]) continue;
            else return tmp.push_back(P(X[now], max(i, dp[i])));
        }
    }
    if(!tmp.size()) return impossible;
    sort(tmp.begin(), tmp.end());
    return tmp[0];
}

int main(){
    ll N;
    cin >> N;
    edge.resize(N);
    X.resize(N);
    for(ll i = 1; i < N; i++){
        ll p;
        cin >> p;
        edge[i].push_back(--p);
        edge[p].push_back(i);
    }
    for(ll &x : X) cin >> x;
    P ans = dfs(0, -1);
    if(ans == impossible) cout << "IM";
    cout << "POSSIBLE\n";
    return 0;
}


Compiler output:
a.cc: In function 'P dfs(ll, ll)':
a.cc:33:38: error: could not convert 'tmp.std::vector<std::pair<long int, long int> >::push_back(std::pair<long int, long int>((* & X.std::vector<long int>::operator[](((std::vector<long int>::size_type)now))), (* & std::max<long int>(i, (*(const long int*)(& dp.std::vector<long int>::operator[](((std::vector<long int>::size_type)i))))))))' from 'void' to 'P' {aka 'std::pair<long int, long int>'}
   33 |             else return tmp.push_back(P(X[now], max(i, dp[i])));
      |                         ~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~
      |                                      |
      |                                      void
Language: C++

#include<cstdio>
#include<cstring>
#include<algorithm>
#include<cmath>
#define min(a,b) ((a)<(b)?(a):(b))
#define reg register
#define file(x) freopen(x".in","r",stdin);freopen(x".out","w",stdout);
#define endfile fclose(stdin);fclose(stdout);
const int MN=1005;
const int inf=0x3f3f3f3f;
int n,a[MN],f[MN],g[2][MN*5];
int to[MN],nxt[MN],h[MN],cnt;
inline void ins(int s,int t){to[++cnt]=t;nxt[cnt]=h[s];h[s]=cnt;}
bool dfs(int st){
	if(!h[st]){f[st]=0;return true;}
	for(reg int i=h[st];i;i=nxt[i])if(!dfs(to[i]))return false;
	reg int pos=1;memset(g[1],0x3f,sizeof(g[1]));g[1][0]=0;
	for(reg int i=h[st];i;i=nxt[i]){
		pos^=1;memset(g[pos],0x3f,sizeof(g[pos]));
		for(reg int j=0;j<=a[st];j++){
			if(j>=f[to[i]])g[pos][j]=min(g[pos][j],g[pos^1][j-f[to[i]]]+a[to[i]]);
			if(j>=a[to[i]])g[pos][j]=min(g[pos][j],g[pos^1][j-a[to[i]]]+f[to[i]]);
		}
	}
	reg int res=inf;
	for(reg int i=0;i<=a[st];i++)res=min(res,g[pos][i]);
	if(res==inf)return false;f[st]=res;return true;
}
int main(){
	//file("division");
	for(reg int i=2;i<=n;i++)ins(IO::read(),i);
	for(reg int i=1;i<=n;i++)a[i]=IO::read();
	puts(dfs(1)?"POSSIBLE":"IMPOSSIBLE");
	return 0;
}

Compiler output:
a.cc: In function 'bool dfs(int)':
a.cc:16:21: warning: ISO C++17 does not allow 'register' storage class specifier [-Wregister]
   16 |         for(reg int i=h[st];i;i=nxt[i])if(!dfs(to[i]))return false;
      |                     ^
a.cc:17:17: warning: ISO C++17 does not allow 'register' storage class specifier [-Wregister]
   17 |         reg int pos=1;memset(g[1],0x3f,sizeof(g[1]));g[1][0]=0;
      |                 ^~~
a.cc:18:21: warning: ISO C++17 does not allow 'register' storage class specifier [-Wregister]
   18 |         for(reg int i=h[st];i;i=nxt[i]){
      |                     ^
a.cc:20:29: warning: ISO C++17 does not allow 'register' storage class specifier [-Wregister]
   20 |                 for(reg int j=0;j<=a[st];j++){
      |                             ^
a.cc:25:17: warning: ISO C++17 does not allow 'register' storage class specifier [-Wregister]
   25 |         reg int res=inf;
      |                 ^~~
a.cc:26:21: warning: ISO C++17 does not allow 'register' storage class specifier [-Wregister]
   26 |         for(reg int i=0;i<=a[st];i++)res=min(res,g[pos][i]);
      |                     ^
a.cc: In function 'int main()':
a.cc:31:21: warning: ISO C++17 does not allow 'register' storage class specifier [-Wregister]
   31 |         for(reg int i=2;i<=n;i++)ins(IO::read(),i);
      |                     ^
a.cc:31:38: error: 'IO' has not been declared
   31 |         for(reg int i=2;i<=n;i++)ins(IO::read(),i);
      |                                      ^~
a.cc:32:21: warning: ISO C++17 does not allow 'register' storage class specifier [-Wregister]
   32 |         for(reg int i=1;i<=n;i++)a[i]=IO::read();
      |                     ^
a.cc:32:39: error: 'IO' has not been declared
   32 |         for(reg int i=1;i<=n;i++)a[i]=IO::read();
      |                                       ^~
Language: C++

#include <iostream>
#include<cstdio>
#include<vector>
#define inf 0x3f3f3f3f
using namespace std;
思路：就是，对每一个节点i，在子树(包括i)中和它同色的权值和固定了，此时，
要使子树中和它异色的权值和越小越好，这样以便给在其上方的节点更多选择的余地，
所以用状态dp[i]，表示i节点的子树中和它异色的最小权值和是多少，
其实也就是求i节点的子树(不包括i)中和它同色的不超过w[i]的最大权值和tmp，
那么dp[i]=sum-tmp;

(其中sum=,j为i的直接子节点)
vector<int> sons[1010];
int w[1010],dp[1010];
int tmp[1010][5050];
bool ok=true;

void dfs(int x){
  int sum=0;
  for(int i=0;i<(int)sons[x].size();i++) dfs(sons[x][i]);
  if(!ok) return;//在ok已经是false的状态下，不要再进行tmp的计算了，否则会导致sum爆int，引起一系列问题，比如RE
  for(int i=0;i<(int)sons[x].size();i++){
    int son=sons[x][i];
    sum+=(w[son]+dp[son]);
    for(int j=0;j<=w[x];j++){
        tmp[i+1][j]=-inf;
        //tmp的状态转移方程
        if(j>=w[son]) tmp[i+1][j]=max(tmp[i+1][j],tmp[i][j-w[son]]+w[son]);
        if(j>=dp[son]) tmp[i+1][j]=max(tmp[i+1][j],tmp[i][j-dp[son]]+dp[son]);
    }
  }
  if(tmp[sons[x].size()][w[x]]<0) ok=false,dp[x]=inf;
  else dp[x]=sum-tmp[sons[x].size()][w[x]];
}

int main()
{
    int n;scanf("%d",&n);
    for(int i=2;i<=n;i++){
        int p;scanf("%d",&p);
        sons[p].push_back(i);
    }
    for(int i=1;i<=n;i++) scanf("%d",&w[i]);
    dfs(1);
    if(ok) printf("POSSIBLE\n");
    else printf("IMPOSSIBLE\n");
    return 0;
}

Compiler output:
a.cc:6:34: error: expected constructor, destructor, or type conversion before '(' token
    6 | 思路：就是，对每一个节点i，在子树(包括i)中和它同色的权值和固定了，此时，
      |                                  ^
a.cc:12:9: error: expected ')' before '=' token
   12 | (其中sum=,j为i的直接子节点)
      | ~       ^
      |         )
a.cc: In function 'void dfs(int)':
a.cc:20:22: error: 'sons' was not declared in this scope
   20 |   for(int i=0;i<(int)sons[x].size();i++) dfs(sons[x][i]);
      |                      ^~~~
a.cc:22:22: error: 'sons' was not declared in this scope
   22 |   for(int i=0;i<(int)sons[x].size();i++){
      |                      ^~~~
a.cc:32:10: error: 'sons' was not declared in this scope
   32 |   if(tmp[sons[x].size()][w[x]]<0) ok=false,dp[x]=inf;
      |          ^~~~
a.cc: In function 'int main()':
a.cc:41:9: error: 'sons' was not declared in this scope
   41 |         sons[p].push_back(i);
      |         ^~~~
Language: C++

#include<iostream>
#include<stdio.h>
#include<string.h>
#include<algorithm>
#include<stdlib.h>
#define maxn 1020
#define N 99999999999
using namespace std;
int n,tot;
inline int read(){

    int x = 0,f = 1; char c = getchar();
    while ((c < '0' || c > '9') && c != EOF) {if (c == '-') f = -1;c = getchar();}

    while ((c <='9' && c >='0') && c != EOF) {x = x * 10 + c - '0';c = getchar();}
    return x * f;
}
int head[maxn],nex[maxn],to[maxn],v[maxn];
void add(int x,int y)
{
    nex[tot]=head[x];
	to[++tot]=y;
	 head[x]=tot;
}
int dp[maxn][maxn*5],temp[maxn*5];
int dfs(int r)
{
	dp[r][0]=0;
	for(int i=head[r];i;i=nex[i])
	{
		int w=dfs(to[i]),b=v[to[i]];

		memcpy(temp,dp[r],sizeof(temp));
		memset(dp[r],ox3f,sizeof(dp[r]));

		for(int j=0;j<=v[r];j++)
		{
			if(j+w<=v[r])
            {if(temp[j]+b<dp[r][j+w])
            {
                dp[r][j+w]=temp[j]+b;
            }
               }
			if(j+b<=v[r])
            {
                if(dp[r][j+b]>temp[j]+w)
                {
                   dp[r][j+b]=temp[j]+w;
                }
            }

		}

	}

	int ans=dp[0][0];

	for(int i=0;i<=v[r];i++)
    {
        if(ans>dp[r][i])
        {
           ans=dp[r][i];
        }
    }
	return ans;
}
int main()
{
	memset(dp,ox3f,sizeof(dp));
    n=read();
	for(int i=2;i<=n;i++)
	{
		int x;
		x=read();
		add(x,i);
	}
	for(int i=1;i<=n;i++)
        v[i]=read();
        int p=0;
	int res=dfs(p+1);
	if(res<dp[0][0])
		return printf("POSSIBLE\n"),0;
	printf("IMPOSSIBLE\n");
}


Compiler output:
a.cc: In function 'int dfs(int)':
a.cc:34:30: error: 'ox3f' was not declared in this scope
   34 |                 memset(dp[r],ox3f,sizeof(dp[r]));
      |                              ^~~~
a.cc: In function 'int main()':
a.cc:69:19: error: 'ox3f' was not declared in this scope
   69 |         memset(dp,ox3f,sizeof(dp));
      |                   ^~~~
Language: C++

#include <bits/stdc++.h>
using namespace std;
const int maxn=1e3+10;
vector<int>g[maxn];
int n,v[maxn],dp[maxn][5010],f[maxn];
int dfs(int pos){
    dp[pos][0]=0;
    for (auto u:g[pos]){
        int w=dfs(u),k=v[u];
        
        memcpy(f,dp[pos],sizeof(f));
        memset(dp[pos],0x3f3f,sizeof(dp[pos]));
        
        for (int j=0; j<=v[pos]; j++){
            if(j+w<=v[pos]) dp[i][j+w]=min(dp[i][j+w],f[j]+k);
            if(j+k<=v[pos]) dp[i][j+k]=min(dp[i][j+k],f[j]+w);
        }
    }
    
    int ans=dp[0][0];
    for (int i=0; i<=v[pos]; i++)
        ans=min(ans,dp[pos][i]);
    return ans;
}
int main(){
    scanf("%d",&n);
    for (int p,i=2; i<=n; i++){
        scanf("%d",&p);
        g[p].push_back(i);
    }
    for (int i=1; i<=n; i++) scanf("%d",&v[i]);
    memset(dp,0x3f3f,sizeof(dp));


    if(dfs(1)<dp[0][0]) puts("POSSIBLE");
    else puts("IMPOSSIBLE");
    return 0;
}


Compiler output:
a.cc: In function 'int dfs(int)':
a.cc:15:32: error: 'i' was not declared in this scope
   15 |             if(j+w<=v[pos]) dp[i][j+w]=min(dp[i][j+w],f[j]+k);
      |                                ^
a.cc:16:32: error: 'i' was not declared in this scope
   16 |             if(j+k<=v[pos]) dp[i][j+k]=min(dp[i][j+k],f[j]+w);
      |                                ^
Language: C++

#include <algorithm>
#include <cstring>
#include <deque>
#include <functional>
#include <iostream>
#include <map>
#include <numeric>
#include <queue>
#include <set>
#include <vector>
using namespace std;
using ll = long long;

int main() {
  int N;
  while (cin >> N) {
    vector<vector<int>> G(N);
    for (int i = 1; i < N; i++) {
      int p;
      cin >> p;
      --p;
      G[p].push_back(i);
    }
    vector<int> X(N);
    for (int i = 0; i < N; i++) {
      cin >> X[i];
    }
    function<int(int)> solve = [&](int v) {
      int sum = 0;
      bitset<5010> dp;
      dp.set(0);
      for (int u : G[v]) {
        int x0 = X[u];
        int x1 = solve(u);
        if (x1 < 0) {
          return -1;
        }
        sum += x0 + x1;
        dp = (dp << x0) | (dp << x1);
      }
      for (int x = X[v]; x >= 0; x--) {
        if (dp[x]) {
          return sum - x;
        }
      }
      return -1;
    };
    cout << (solve(0) < 0 ? "IMPOSSIBLE" : "POSSIBLE") << endl;
  }
  return 0;
}


Compiler output:
a.cc: In lambda function:
a.cc:30:7: error: 'bitset' was not declared in this scope
   30 |       bitset<5010> dp;
      |       ^~~~~~
a.cc:10:1: note: 'std::bitset' is defined in header '<bitset>'; this is probably fixable by adding '#include <bitset>'
    9 | #include <set>
  +++ |+#include <bitset>
   10 | #include <vector>
a.cc:30:20: error: 'dp' was not declared in this scope
   30 |       bitset<5010> dp;
      |                    ^~
Language: C++

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <string>
#include <vector>
#include <map>
#include <set>
using namespace std;

int main() {
        int n;
        scanf("%d", &n);
        vector<vector<int>> g(n);
        for (int i = 1; i < n; i ++) {
                int p;
                scanf("%d", &p);
                p --;
                g[p].push_back(i);
        }
        vector<int> x(n);
        for (int i = 0; i < n; i ++) {
                scanf("%d", &x[i]);
        }
        vector<int> res(n);
        function<void (int)> dfs = [&](int u) {
                vector<int> dp(x[u] + 1, 1 << 30);
                dp[0] = 0;
                for (auto v : g[u]) {
                        dfs(v);
                        vector<int> prev = dp;
                        dp.assign(x[u] + 1, 1 << 30);
                        int a = x[v];
                        int b = res[v];
                        for (int i = 0; i < prev.size(); i ++) if (prev[i] < 1 << 30) {
                                if (i + a < x[u]) dp[i + a] = min(dp[i + a], prev[i] + b);
                                if (i + b < x[u]) dp[i + b] = min(dp[i + b], prev[i] + a);
                        }
                }
                int mi = 1 << 30;
                for (int i = 0; i < dp.size(); i ++) {
                        mi = min(mi, dp[i]);
                }
                res[u] = mi;
        };
        dfs(0);
        bool ans = res[0] < 1 << 30;
        puts(ans ? "POSSIBLE" : "IMPOSSIBLE");
        return 0;
}



Compiler output:
a.cc: In function 'int main()':
a.cc:25:9: error: 'function' was not declared in this scope
   25 |         function<void (int)> dfs = [&](int u) {
      |         ^~~~~~~~
a.cc:8:1: note: 'std::function' is defined in header '<functional>'; this is probably fixable by adding '#include <functional>'
    7 | #include <set>
  +++ |+#include <functional>
    8 | using namespace std;
a.cc:25:18: error: expected primary-expression before 'void'
   25 |         function<void (int)> dfs = [&](int u) {
      |                  ^~~~
a.cc:45:9: error: 'dfs' was not declared in this scope
   45 |         dfs(0);
      |         ^~~
Language: C++

int n,x[5010],y[5010];
int tote,FIR[5010],TO[5010],NEXT[5010];
bool vis[5010];

void addedge(int u,int v)
{
	TO[++tote]=v;
	NEXT[tote]=FIR[u];
	FIR[u]=tote;
}

bool dfs(int u)
{
	for (int p=FIR[u];p;p=NEXT[p])
	{
		int v=TO[p];
		if (!dfs(v)) return 0;
	}
	memset(vis,0,sizeof(vis));
	vis[0]=1;
	int i,S0=0,S1=0;
	for (int p=FIR[u];p;p=NEXT[p])
	{
		int v=TO[p];
		S0+=min(x[v],y[v]);
		S1+=max(x[v],y[v]);
		int tmp=abs(x[v]-y[v]);
		for (i=x[u]-tmp;i>=0;i--)
			vis[i+tmp]|=vis[i];
	}
	if (S0>x[u]) return 0;
	for (i=x[u]-S0;i>=0;i--)
		if (vis[i]) {y[u]=S1-i; break;}
	return 1;
}

int main()
{
#ifdef h10
	freopen("E.in","r",stdin);
	freopen("E.out","w",stdout);
#endif
	int i,f;
	scanf("%d",&n);
	for (i=2;i<=n;i++)
	{
		scanf("%d",&f);
		addedge(f,i);
	}
	for (i=1;i<=n;i++)
		scanf("%d",&x[i]);
	puts(dfs(1)?"POSSIBLE":"IMPOSSIBLE");
}


Compiler output:
a.cc: In function 'bool dfs(int)':
a.cc:19:9: error: 'memset' was not declared in this scope
   19 |         memset(vis,0,sizeof(vis));
      |         ^~~~~~
a.cc:1:1: note: 'memset' is defined in header '<cstring>'; this is probably fixable by adding '#include <cstring>'
  +++ |+#include <cstring>
    1 | int n,x[5010],y[5010];
a.cc:25:21: error: 'min' was not declared in this scope
   25 |                 S0+=min(x[v],y[v]);
      |                     ^~~
a.cc:26:21: error: 'max' was not declared in this scope
   26 |                 S1+=max(x[v],y[v]);
      |                     ^~~
a.cc:27:25: error: 'abs' was not declared in this scope
   27 |                 int tmp=abs(x[v]-y[v]);
      |                         ^~~
a.cc: In function 'int main()':
a.cc:44:9: error: 'scanf' was not declared in this scope
   44 |         scanf("%d",&n);
      |         ^~~~~
a.cc:52:9: error: 'puts' was not declared in this scope
   52 |         puts(dfs(1)?"POSSIBLE":"IMPOSSIBLE");
      |         ^~~~
Language: C++

#include <cstdio>
#include <Cstring>
#include <algorithm>
#define MAXN 1010
#define MAXM 5010
using namespace std;

int n;
int p[MAXN],a[MAXN],b[MAXN],f[MAXN][MAXM];

bool gao(int x){
	b[x]=MAXM;
	for(int i=0;i<=a[x];i++)
		if(f[x][i]<b[x]) b[x]=f[x][i];
	if(b[x]>=MAXM) return 0;
	return 1;
}

void trans(int x){
	int y=p[x];
	for(int i=a[y];i>=0;i--){
		int temp=MAXM;
		if(i>=a[x]) temp=min(temp,f[y][i-a[x]]+b[x]);
		if(i>=b[x]) temp=min(temp,f[y][i-b[x]]+a[x]);
		f[y][i]=temp;
	}
}

int main(){
	scanf("%d",&n);
	for(int i=2;i<=n;i++) scanf("%d",p+i);
	for(int i=1;i<=n;i++) scanf("%d",a+i);
	for(int i=n;i>=1;i--){
		if(!gao(i)){
			puts("IMPOSSIBLE");
			return 0;
		}
		if(i>1) trans(i);
	}
	puts("POSSIBLE");
	return 0;
}


Compiler output:
a.cc:2:10: fatal error: Cstring: No such file or directory
    2 | #include <Cstring>
      |          ^~~~~~~~~
compilation terminated.
Language: C++

#include<cmath>
#include<cstdio>
#include<cstring>
#include<iostream>
#include<algorithm>
#define inf 1e9
using namespace std;
inline void down(int &x,const int &y){
	if(x>y){
		x=y;
	}
}
int n;
struct edge{
	int y,nex;
}a[2003];
int len,fir[1003];
inline void ins(const int x,const int y){
	a[++len]=(edge){y,fir[x]};fir[x]=len;
}
int f[1003],w[1003],g[2][5003];
inline void clear(const int now){
	for(int i=0;i<maxv;i++){
		g[now][i]=inf;
	}
}
bool dp(const int x){
    if(!fir[x]){
		f[x]=0;
		return 1;
	}
    int now=1;
	clear(1),g[1][0]=0;
	for(int k=fir[x],y=a[k].y;k;k=a[k].nex,y=a[k].y){
		if(!dp(y)){
			return 0;
		}
		now=!now;
		clear(now);
		for(int i=0;i<=w[x];i++){
			if(i>=w[y]){
				down(g[now][i],g[!now][i-w[y]]+f[y]);
			}
			if(i>=f[y]){
				down(g[now][i],g[!now][i-f[y]]+w[y]);
			}
        }
    }
    for(int i=0;i<=w[x];i++){
    	down(f[x],g[now][i]);
	}
    if(f[x]==inf){
    	return 0;
	}else{
		return 1;
	}
}
int main(){
    cin>>n;
    for(int i=2;i<=n;i++){
        int x;
        cin>>x;
        ins(x,i);
    }
    for(int i=1;i<=n;i++){
		cin>>w[i];
	}
    if(!dp(1)){
    	cout<<"IMPOSSIBLE"<<endl;
	}else{
		cout<<"POSSIBLE"<<endl;
	}
    return 0;
}

Compiler output:
a.cc: In function 'void clear(int)':
a.cc:23:23: error: 'maxv' was not declared in this scope
   23 |         for(int i=0;i<maxv;i++){
      |                       ^~~~
Language: C++

#include <algorithm>
#include <cstdio>
#include <iostream>
#include <set>
#include <utility>
#include <vector>
#include <queue>
#include <cmath>
#include <stack>
#include <deque>
#include <unordered_map>
#include <map>
#include <bitset>
#include <string>
#include <cstring>

#define pb push_back
#define mp make_pair
#define l(x) x << 1
#define r(x) x << 1 | 1
#define scan(x) do {while((x=getchar())<'0') ; for(x-='0'; '0'<=(_=getchar()); x=(x<<3)+(x<<1)+_-'0') ; } while(0)
char _;
#define x first
#define y second

using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int, int> pii;
typedef pair<float, float> pff;
typedef pair<double, double> pdd;
typedef pair<ll, ll> pll;
typedef map<int, int> mii;
typedef unordered_map<int, int> umii;

int N, x[1005], u, dp1[1005], dp2[1005][5005];
vector<int> adj[1005];
bool v = 1;

int go2(int i, int j, int k) {
    if (adj[i].size() <= j) {
        return 0;
    }
    u = adj[i][j];
    if (dp2[u][k] != -1) {
        return dp2[u][k];
    }

    int ret = 1 << 25;
    if (k - dp1[u] >= 0) {
        ret = min(ret, go2(i, j + 1, k - dp1[u]) + x[u]);
    }
    if (k - x[u] >= 0) {
        ret = min(ret, go2(i, j + 1, k - x[u]) + dp1[u]);
    }
    return dp2[u][k] = ret;
}

void go1(int i) {
    if (adj[i].empty()) {
        dp[i] = 0;
        return;
    }
    for (int j = 0; j < adj[i].size(); j++) {
        go1(adj[i][j]);
    }
    int ret = go2(i, 0, x[i]);
    v &= ret < 1 << 25;
    dp1[i] = ret;
}

int main() {
    scanf("%d", &N);
    for (int i = 2; i <= N; i++) {
        scanf("%d", &u);
        adj[u].pb(i);
    }
    for (int i = 1; i <= N; i++) {
        scanf("%d", &x[i]);
    }
    memset(dp1, -1, sizeof dp1);
    memset(dp2, -1, sizeof dp2);
    go1(1);
    printf("%s\n", dp1[1] < 1 << 25 ? "POSSIBLE" : "IMPOSSIBLE");
}


Compiler output:
a.cc: In function 'void go1(int)':
a.cc:61:9: error: 'dp' was not declared in this scope; did you mean 'dp2'?
   61 |         dp[i] = 0;
      |         ^~
      |         dp2
Language: C++

#include <algorithm>
#include <cstdio>
#include <iostream>
#include <set>
#include <utility>
#include <vector>
#include <queue>
#include <cmath>
#include <stack>
#include <deque>
#include <unordered_map>
#include <map>
#include <bitset>
#include <string>
#include <cstring>

#define pb push_back
#define mp make_pair
#define l(x) x << 1
#define r(x) x << 1 | 1
#define scan(x) do {while((x=getchar())<'0') ; for(x-='0'; '0'<=(_=getchar()); x=(x<<3)+(x<<1)+_-'0') ; } while(0)
char _;
#define x first
#define y second

using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int, int> pii;
typedef pair<float, float> pff;
typedef pair<double, double> pdd;
typedef pair<ll, ll> pll;
typedef map<int, int> mii;
typedef unordered_map<int, int> umii;

int N, x[1005], u, dp1[1005], dp2[1005][5005];
vector<int> adj[1005];
bool v = 1;

int go2(int i, int j, int k) {
    if (adj[i].size() <= j) {
        return 0;
    }
    u = adj[i][j];
    if (dp2[u][k] != -1) {
        return dp2[u][k];
    }

    int ret = 1 << 25;
    if (k - dp1[u] >= 0) {
        ret = min(ret, go2(i, j + 1, k - dp1[u]) + x[u]);
    }
    if (k - x[u] >= 0) {
        ret = min(ret, go2(i, j + 1, k - x[u]) + dp1[u]);
    }
    return dp2[u][k] = ret;
}

void go1(int i) {
    if (adj[i].empty()) {
        return dp1[i] = 0;
    }
    if (dp1[i] != -1) {
        return dp1[i];
    }
    for (int j = 0; j < adj[i].size(); j++) {
        go1(adj[i][j]);
    }
    int ret = go2(i, 0, x[i]);
    v &= ret < 1 << 25;
    dp1[i] = ret;
}

int main() {
    scanf("%d", &N);
    for (int i = 2; i <= N; i++) {
        scanf("%d", &u);
        adj[u].pb(i);
    }
    for (int i = 1; i <= N; i++) {
        scanf("%d", &x[i]);
    }
    memset(dp1, -1, sizeof dp1);
    memset(dp2, -1, sizeof dp2);
    go1(1);
    printf("%s\n", dp1[1] < 1 << 25 ? "POSSIBLE" : "IMPOSSIBLE");
}


Compiler output:
a.cc: In function 'void go1(int)':
a.cc:61:23: error: return-statement with a value, in function returning 'void' [-fpermissive]
   61 |         return dp1[i] = 0;
      |                ~~~~~~~^~~
a.cc:64:21: error: return-statement with a value, in function returning 'void' [-fpermissive]
   64 |         return dp1[i];
      |                ~~~~~^
Language: C++

#include<ctime>
#include<iostream>
#include<algorithm>
#include<cstdio>
#include<cstdlib>
#include<cmath> 
#include<cstring> 
#include<cassert>
#include<string>
#include<sstream>
#include<fstream>
#include<deque>
#include<queue>
#include<vector>
#include<map>
#include<list>
#include<stack>
#include<set>
#include<bitset>
#include<iomanip>
#include<utility>
#include<functional>
#include<cctype>
#include<cerrno>
#include<cfloat>
#include<ciso646>
#include<climits>
#include<clocale>
#include<complex>
#include<csetjmp>
#include<csignal>
#include<cstdarg>
#include<cstddef>
#include<cwchar>
#include<cwctype>
#include<exception>
#include<locale>
#include<numeric>
#include<new>
#include<stdexcept>
#include<limits>
using namespace std;

#define ll long long
#define INF 1e9
#define rep(i,n) for(int (i)=0;(i)<n;i++)
#define REP(i,n) for(int (i)=1;(i)<=n;i++)
#define mk(a,b) make_pair(a,b)
#define fi first
#define se second
#define pii pair<int,int>
#define sz(s) s.size()
#define all(s) (s.begin(),s.end())
inline void Fail(){
	printf("IMPOSSIBLE");
	exit(0);
}

const int maxn=1005;
const int maxm=5005;
int n;
vector<int>edge[maxn];
int dp[2][maxn],w[maxn],tmp[2][maxn][maxm];

void dfs(int x,int p){
	vector<int>son;
	rep(i,edge[x].size()){
		int y=edge[x][i];
		if(y==p)continue;
		dfs(y,x);
		son.push_back(y);
	}
	if(son.empty()){
		dp[0][x]=dp[1][x]=0;
		return;
	}
	rep(i,son.size())rep(j,w[x]+1)rep(k,2)tmp[k][i][j]=INF;
	int mn[2]={INF,INF};
	rep(k,2)rep(i,son.size())rep(j,w[x]+1){
		if(j>=w[son[i]])tmp[k][i][j]=min(tmp[k][i][j],(!i?0:tmp[k][i-1][j-w[son[i]]])+dp[k^1][son[i]]);
		if(j>=dp[k][son[i]])tmp[k][i][j]=min(tmp[k][i][j],(!i?0:tmp[k][i-1][j-dp[k][son[i]]])+w[son[i]]);
		if(i==son.size()-1)mn[k]=min(mn[k],tmp[k][i][j]);
	}
	if(mn[0]==INF&&mn[1]==INF)Fail();
	dp[1][x]=mn[0];
	dp[0][x]=mn[1];
//	printf("%d %d %d\n",x,dp[0][x],dp[1][x]);
}

int main(){
	scanf("%d",&n);
	for(int i=2;i<=n;i++){
		int p;
		scanf("%d",&p);
		edge[p].push_back(i);
		edge[i].push_back(p);
	}
	REP(i,n)scanf("%d",&w[i]);
	dfs(1,-1);
	printf("POSSIBLE");
	return 0;
}

Compiler output:
a.cc: In function 'void dfs(int, int)':
a.cc:45:13: error: narrowing conversion of '1.0e+9' from 'double' to 'int' [-Wnarrowing]
   45 | #define INF 1e9
      |             ^~~
a.cc:78:20: note: in expansion of macro 'INF'
   78 |         int mn[2]={INF,INF};
      |                    ^~~
a.cc:45:13: error: narrowing conversion of '1.0e+9' from 'double' to 'int' [-Wnarrowing]
   45 | #define INF 1e9
      |             ^~~
a.cc:78:24: note: in expansion of macro 'INF'
   78 |         int mn[2]={INF,INF};
      |                        ^~~
Language: C++

#include<stdio.h>
#include<algorithm>
#include<cmath>
#include<cstring>
#include<cstdlib>
#define N 1005
#define inf 1000000000
#define lowbit(o) o&(-o)
using namespace std;
int i,j,k,l,s,n,m,tot,last[N],x,next[N],to[N],a[N],f[N][5005];
struct node {
	int a[3];
}A[N];
inline void add(int x,int y) {
	next[++tot]=last[x]; last[x]=tot; to[tot]=y;
}
inline void Min(int &x,int y) {
	x=min(x,y);
}
int main() {
	scanf("%d",&n);
	for (i=2;i<=n;i++) scanf("%d",&x),add(x,i);
	for (i=1;i<=n;i++) scanf("%d",&a[i]);
	for (i=n;i;i--) {
		for (j=1;j<=a[i];j++) f[0][j]=inf;
		f[0][0]=tot=0;
		for (j=last[i];j;j=next[j]) {
			++tot;
			for (k=0;k<=a[i];k++) f[tot][k]=inf;
			for (k=0;k<=a[i]-A[to[j]].a[1];k++) Min(f[tot][k+A[to[j]].a[1]],f[tot-1][k]+A[to[j]].a[2]);
			for (k=0;k<=a[i]-A[to[j]].a[2];k++) Min(f[tot][k+A[to[j]].a[2]],f[tot-1][k]+A[to[j]].a[1]);
		}
		A[i].a[2]=inf;
		for (j=0;j<=a[i];j++) Min(A[i].a[2],f[tot][j]);
		if (A[i].a[2]==inf) return puts("IMPOSSIBLE"),0;
		A[i].a[1]=a[i];
	}
	puts("POSSIBLE");
}


Compiler output:
a.cc: In function 'void add(int, int)':
a.cc:15:9: error: reference to 'next' is ambiguous
   15 |         next[++tot]=last[x]; last[x]=tot; to[tot]=y;
      |         ^~~~
In file included from /usr/include/c++/14/bits/stl_algobase.h:66,
                 from /usr/include/c++/14/algorithm:60,
                 from a.cc:2:
/usr/include/c++/14/bits/stl_iterator_base_funcs.h:232:5: note: candidates are: 'template<class _InputIterator> constexpr _InputIterator std::next(_InputIterator, typename iterator_traits<_Iter>::difference_type)'
  232 |     next(_InputIterator __x, typename
      |     ^~~~
a.cc:10:33: note:                 'int next [1005]'
   10 | int i,j,k,l,s,n,m,tot,last[N],x,next[N],to[N],a[N],f[N][5005];
      |                                 ^~~~
a.cc: In function 'int main()':
a.cc:27:36: error: reference to 'next' is ambiguous
   27 |                 for (j=last[i];j;j=next[j]) {
      |                                    ^~~~
/usr/include/c++/14/bits/stl_iterator_base_funcs.h:232:5: note: candidates are: 'template<class _InputIterator> constexpr _InputIterator std::next(_InputIterator, typename iterator_traits<_Iter>::difference_type)'
  232 |     next(_InputIterator __x, typename
      |     ^~~~
a.cc:10:33: note:                 'int next [1005]'
   10 | int i,j,k,l,s,n,m,tot,last[N],x,next[N],to[N],a[N],f[N][5005];
      |                                 ^~~~
Language: C++

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N = 5e5+1;


int n,fa[N],tot[N],fr[N],a[N],b[N],c[N],cnt,head[N];

st	ruct nd{int ne,to;}e[N];

void in(int x,int y){e[++cnt].to=y;e[cnt].ne=head[x];head[x]=cnt;}
int w1[5001],q[N];
void dfs(int x)
{
	for(int i=head[x];i;i=e[i].ne)dfs(e[i].to);
	if(!fr[x])return;
	q[0]=0;
	int ret=tot[x],tot1=0;
	for(int i=head[x];i;i=e[i].ne)
	{
		ret-=min(a[e[i].to],b[e[i].to]);
		q[++q[0]]=abs(a[e[i].to]-b[e[i].to]);
		tot1+=a[e[i].to]+b[e[i].to];
	}
	if(ret<0){cout<<"IMPOSSIBLE";exit(0);}
	memset(w1,0,sizeof(0));
	w1[0]=1;
	for(int i=1;i<=q[0];++i)
	for(int t=5000;t>=q[i];--t)
	if(w1[t-q[i]]==1)w1[t]=1;
	for(int i=ret;i>=0;--i)
	if(w1[i]==x){ret-=i;break;}
	a[x]=tot[x];b[x]=tot1+ret-a[x];
	return;
}

int main()
{
	scanf("%d",&n);
	for(int i=2;i<=n;++i)
	scanf("%d",&fa[i]),in(fa[i],i),fr[fa[i]]++;
	for(int i=1;i<=n;++i)
	{
		scanf("%d",&tot[i]);
		if(!fr[i])a[i]=tot[i],b[i]=0;
	}
	dfs(1);
	cout<<"POSSIBLE";


}

Compiler output:
a.cc:9:1: error: 'st' does not name a type
    9 | st      ruct nd{int ne,to;}e[N];
      | ^~
a.cc:9:28: error: 'e' does not name a type
    9 | st      ruct nd{int ne,to;}e[N];
      |                            ^
a.cc: In function 'void in(int, int)':
a.cc:11:22: error: 'e' was not declared in this scope
   11 | void in(int x,int y){e[++cnt].to=y;e[cnt].ne=head[x];head[x]=cnt;}
      |                      ^
a.cc: In function 'void dfs(int)':
a.cc:15:31: error: 'e' was not declared in this scope
   15 |         for(int i=head[x];i;i=e[i].ne)dfs(e[i].to);
      |                               ^
a.cc:19:31: error: 'e' was not declared in this scope
   19 |         for(int i=head[x];i;i=e[i].ne)
      |                               ^