Problem p02665 (C++) — buggy submission, verdict: Runtime Error

/*
これを入れて実行
g++ code.cpp
./a.out
 */

#include <algorithm>
#include <bitset>
#include <cassert>
#include <cmath>
#include <cstring>
#include <deque>
#include <functional>
#include <iomanip>
#include <iostream>
#include <map>
#include <math.h>
#include <queue>
#include <set>
#include <stack>
#include <stdio.h>
#include <string>
#include <tuple>
#include <unordered_map>
#include <utility>
#include <vector>

#define all(x) (x).begin(), (x).end()
#define rep(i, n) for (int i = 0; i < (int)(n); i++)

using namespace std;
typedef long long ll;
typedef long double ld;

int dy4[4] = {-1, 0, +1, 0};
int dx4[4] = {0, +1, 0, -1};
int dy8[8] = {-1, -1, 0, 1, 1, 1, 0, -1};
int dx8[8] = {0, 1, 1, 1, 0, -1, -1, -1};

const long long INF = 1LL << 62;
// const ll MOD = 1e9 + 7;

bool greaterSecond(const pair<int, int> &f, const pair<int, int> &s) {
  return f.second > s.second;
}

ll gcd(ll a, ll b) {
  if (b == 0)
    return a;
  return gcd(b, a % b);
}

ll lcm(ll a, ll b) { return a / gcd(a, b) * b; }

ll conbinationMemo[100][100];

void cmemoInit() {
  rep(i, 100) {
    rep(j, 100) { conbinationMemo[i][j] = -1; }
  }
}

ll nCr(ll n, ll r) {
  if (conbinationMemo[n][r] != -1)
    return conbinationMemo[n][r];
  if (r == 0 || r == n) {
    return 1;
  } else if (r == 1) {
    return n;
  }
  return conbinationMemo[n][r] = (nCr(n - 1, r) + nCr(n - 1, r - 1));
}

ll nPr(ll n, ll r) {
  r = n - r;
  ll ret = 1;
  for (ll i = n; i >= r + 1; i--)
    ret *= i;
  return ret;
}
//-----------------------ここから-----------
ll n;
vector<ll> a;
int main(void) {
  cin >> n;
  a.resize(n + 1);
  rep(i, n + 1) cin >> a[i];
  bool ok = true;
  if (n == 0) {
    if (a[0] != 1) {
      cout << -1 << endl;
    } else {
      cout << 1 << endl;
    }
    return 0;
  } else {
    if (a[0] != 0) {
      ok = false;
    }
  }
  if (!ok) {
    cout << -1 << endl;
    return 0;
  }
  vector<ll> sum(n + 2, 0);
  for (int i = 0; i <= n; i++) {
    sum[i + 1] = a[i] + sum[i];
  }
  ll last = a[n];
  ll now = 1;
  ll ans = 1;
  for (ll i = 1; i <= n; i++) {
    // cout << now << endl;
    if (now * 2 < a[i]) {
      ok = false;
      break;
    }
    ll rest = sum[n + 1] - sum[i];
    ll tmp = now * 2;
    // cout << tmp << " " << rest << endl;
    now = min(tmp, rest);
    // cout << "plus"<< now << endl;
    ans += now;
    now -= a[i];
    // cout << now << endl;
  }
  if (!ok) {
    cout << -1 << endl;
  } else {
    cout << ans << endl;
  }
}


Error: 0

Fixed submission:

/*
これを入れて実行
g++ code.cpp
./a.out
 */

#include <algorithm>
#include <bitset>
#include <cassert>
#include <cmath>
#include <cstring>
#include <deque>
#include <functional>
#include <iomanip>
#include <iostream>
#include <map>
#include <math.h>
#include <queue>
#include <set>
#include <stack>
#include <stdio.h>
#include <string>
#include <tuple>
#include <unordered_map>
#include <utility>
#include <vector>

#define all(x) (x).begin(), (x).end()
#define rep(i, n) for (int i = 0; i < (int)(n); i++)

using namespace std;
typedef long long ll;
typedef long double ld;

int dy4[4] = {-1, 0, +1, 0};
int dx4[4] = {0, +1, 0, -1};
int dy8[8] = {-1, -1, 0, 1, 1, 1, 0, -1};
int dx8[8] = {0, 1, 1, 1, 0, -1, -1, -1};

const long long INF = 1LL << 62;
// const ll MOD = 1e9 + 7;

bool greaterSecond(const pair<int, int> &f, const pair<int, int> &s) {
  return f.second > s.second;
}

ll gcd(ll a, ll b) {
  if (b == 0)
    return a;
  return gcd(b, a % b);
}

ll lcm(ll a, ll b) { return a / gcd(a, b) * b; }

ll conbinationMemo[100][100];

void cmemoInit() {
  rep(i, 100) {
    rep(j, 100) { conbinationMemo[i][j] = -1; }
  }
}

ll nCr(ll n, ll r) {
  if (conbinationMemo[n][r] != -1)
    return conbinationMemo[n][r];
  if (r == 0 || r == n) {
    return 1;
  } else if (r == 1) {
    return n;
  }
  return conbinationMemo[n][r] = (nCr(n - 1, r) + nCr(n - 1, r - 1));
}

ll nPr(ll n, ll r) {
  r = n - r;
  ll ret = 1;
  for (ll i = n; i >= r + 1; i--)
    ret *= i;
  return ret;
}
//-----------------------ここから-----------
ll n;
vector<ll> a;
int main(void) {
  cin >> n;
  a.resize(n + 1);
  rep(i, n + 1) cin >> a[i];
  bool ok = true;
  if (n == 0) {
    if (a[0] != 1) {
      cout << -1 << endl;
    } else {
      cout << 1 << endl;
    }
    return 0;
  } else {
    if (a[0] != 0) {
      ok = false;
    }
  }
  if (!ok) {
    cout << -1 << endl;
    return 0;
  }
  vector<ll> sum(n + 2, 0);
  for (int i = 0; i <= n; i++) {
    sum[i + 1] = a[i] + sum[i];
  }
  ll last = a[n];
  ll now = 1;
  ll ans = 1;
  for (ll i = 1; i < n; i++) {
    // cout << now << endl;
    if (now * 2 < a[i]) {
      assert(false);
      ok = false;
      break;
    }
    ll rest = sum[n + 1] - sum[i];
    ll tmp = now * 2;
    // cout << tmp << " " << rest << endl;
    now = min(tmp, rest);
    // cout << "plus"<< now << endl;
    ans += now;
    now -= a[i];
  }
  if (!ok) {
    cout << -1 << endl;
  } else {
    cout << ans + last << endl;
  }
}