Submission #477148

#	Time	Username	Problem	Language	Result	Execution time	Memory
477148		jesus_coconut	Remittance (JOI19_remittance)	C++17	100 / 100	289 ms	36440 KiB

remittance

#include <bits/stdc++.h>
#define all(a) begin(a), end(a)
#define F first
#define S second
#define pb push_back
using namespace std;
using ll = long long;
using ull = unsigned long long;
using pii = pair<int, int>;
int const MOD = 1e9 + 7;
int const N = 500009;


void solve() {
  int n;
  cin >> n;
  vector<ll> a(n), b(n);
  for (int i = 0; i < n; ++i) cin >> a[i] >> b[i];
  if (all_of(all(b), [](ll x) { return x == 0; })) {
    if (all_of(all(a), [](ll x) { return x == 0; })) {
      cout << "Yes\n";
    } else cout << "No\n";
    return;
  }
  while (true) {
    bool rep = false;
    for (int i = 0; i < n; ++i) {
      if (a[i] > b[i]) {
        ll diff = (a[i] - b[i] + 1) / 2;
        a[i] -= 2 * diff;
        a[(i+1) % n] += diff;
        rep = true;
      }
    }
    if ([&]{
      for (int i = 0; i < n; ++i) {
        if (a[i] != b[i]) return false;
      }
      return true;
    }()) {
      cout << "Yes\n";
      return;
    }
    if (!rep) {
      cout << "No\n";
      return;
    }
  }
}

int main() {
  ios::sync_with_stdio(false);
  cin.tie(nullptr);


  solve();
  return 0;
}

• Subtask 1: 15 / 15
• Subtask 2: 40 / 40
• Subtask 3: 45 / 45