#pragma GCC optimize ("O3")
#pragma GCC target ("avx")
#include "bits/stdc++.h" // define macro "/D__MAI"

using namespace std;
typedef long long int ll;

#define xprintf(fmt,...) fprintf(stderr,fmt,__VA_ARGS__)
#define debugv(v) {printf("L%d %s > ",__LINE__,#v);for(auto e:v){cout<<e<<" ";}cout<<endl;}
#define debuga(m,w) {printf("L%d %s > ",__LINE__,#m);for(int x=0;x<(w);x++){cout<<(m)[x]<<" ";}cout<<endl;}
#define debugaa(m,h,w) {printf("L%d %s >\n",__LINE__,#m);for(int y=0;y<(h);y++){for(int x=0;x<(w);x++){cout<<(m)[y][x]<<" ";}cout<<endl;}}
#define ALL(v) (v).begin(),(v).end()
#define repeat(cnt,l) for(auto cnt=0ll;(cnt)<(l);++(cnt))
#define iterate(cnt,b,e) for(auto cnt=(b);(cnt)!=(e);++(cnt))
#define MD 1000000007ll
#define PI 3.1415926535897932384626433832795
#define EPS 1e-12
template<typename T1, typename T2> ostream& operator <<(ostream &o, const pair<T1, T2> p) { o << "(" << p.first << ":" << p.second << ")"; return o; }
template<typename iterator> inline size_t argmin(iterator begin, iterator end) { return distance(begin, min_element(begin, end)); }
template<typename iterator> inline size_t argmax(iterator begin, iterator end) { return distance(begin, max_element(begin, end)); }
template<typename T> T& maxset(T& to, const T& val) { return to = max(to, val); }
template<typename T> T& minset(T& to, const T& val) { return to = min(to, val); }

mt19937_64 randdev(8901016);
inline ll rand_range(ll l, ll h) {
    return uniform_int_distribution<ll>(l, h)(randdev);
}

#ifdef __MAI
#define getchar_unlocked getchar
#define putchar_unlocked putchar
#endif
#ifdef __VSCC
#define getchar_unlocked _getchar_nolock
#define putchar_unlocked _putchar_nolock
#endif
namespace {
#define isvisiblechar(c) (0x21<=(c)&&(c)<=0x7E)
    class MaiScanner {
    public:
        template<typename T> void input_integer(T& var) {
            var = 0;
            T sign = 1;
            int cc = getchar_unlocked();
            for (; cc<'0' || '9'<cc; cc = getchar_unlocked())
                if (cc == '-') sign = -1;
            for (; '0' <= cc&&cc <= '9'; cc = getchar_unlocked())
                var = (var << 3) + (var << 1) + cc - '0';
            var = var*sign;
        }
        inline int c() { return getchar_unlocked(); }
        inline MaiScanner& operator>>(int& var) {
            input_integer<int>(var);
            return *this;
        }
        inline MaiScanner& operator>>(long long& var) {
            input_integer<long long>(var);
            return *this;
        }
        inline MaiScanner& operator>>(string& var) {
            int cc = getchar_unlocked();
            for (; !isvisiblechar(cc); cc = getchar_unlocked());
            for (; isvisiblechar(cc); cc = getchar_unlocked())
                var.push_back(cc);
            return *this;
        }
        template<typename IT> void in(IT begin, IT end) {
            for (auto it = begin; it != end; ++it) *this >> *it;
        }
    };
}
MaiScanner scanner;




// 隣接頂点を保持する有向グラフ
class DGraph {
public:
    size_t n;
    vector<vector<int>> vertex_to;
    vector<vector<int>> vertex_from;

    DGraph(size_t n = 0) :n(n), vertex_to(n), vertex_from(n) {}

    void connect(int from, int to) {
        vertex_to[from].emplace_back(to);
        vertex_from[to].emplace_back(from);
    }
    void resize(size_t _n) {
        n = _n;
        vertex_to.resize(_n);
        vertex_from.resize(_n);
    }
};


ll m, n, kei;
DGraph graph;

int xx[1010];

void bye(string s) {
    cout << s << endl;
    exit(0);
}

int calcdp(const vector<pair<int,int>>& sets, int bound = 5000) {
    vector<int> dp(bound +1, -1);

    dp[0] = 0;
    for (auto p : sets) {
        vector<int> dpt(bound+1, -1);
        for (int i = bound; 0 <= i; --i){
            if (0 <= dp[i]) {
                if (i + p.first <= bound)
                    if (dpt[i + p.first] == -1)
                        dpt[i + p.first] = dp[i] + p.second;
                    else
                        minset(dpt[i + p.first],dp[i] + p.second);
                if (i + p.second <= bound)
                    if (dpt[i + p.second] == -1)
                        dpt[i + p.second] = dp[i] + p.first;
                    else
                        minset(dpt[i + p.second], dp[i] + p.first);
            }
        }
        dp.swap(dpt);
    }
    int best = 1e8;
    for (auto v : dp) {
        if (0 <= v)
            minset(best, v);
    }
    return 1e7 < best ? -1 : best;
}

// @return: #ofSame, #ofNotSame
pair<int, int> dfs(int idx) {
    if (graph.vertex_from[idx].empty()) {
        return make_pair(xx[idx], 0);
    }

    vector<pair<int, int>> childlen;
    for (int from : graph.vertex_from[idx]) {
        auto p = dfs(from); 
        childlen.push_back(p);
    }

    int judge = calcdp(childlen, xx[idx]);
    if (judge == -1)
        bye("IMPOSSIBLE");
    return make_pair(xx[idx], judge);
}

int main() {

    scanner >> n;
    graph.resize(n);

    iterate(i, 1, n) {
        int p;
        scanner >> p;
        --p;
        graph.connect(i, p);
    }

    repeat(i, n) {
        int x;
        scanner >> x;
        xx[i] = x;
    }

    dfs(0);

    cout << "POSSIBLE" << endl;

    return 0;
}

Measured memory_bytes: 384