Submission #1093583

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Source Code Expand

#include <algorithm>
#include <cassert>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <deque>
#include <iostream>
#include <limits>
#include <numeric>
#include <map>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <utility>
#include <vector>

#pragma comment(linker, "/STACK:36777216")

using namespace std;

#define MP make_pair
#define all(v) (v).begin(), (v).end()
#define PROBLEM_ID "A"

typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<vvi> vvvi;
typedef vector<bool> vb;
typedef long double ld;
typedef pair<int, int> pii;
typedef long long ll;
typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef vector<vvl> vvvl;
typedef pair<ll, ll> pll;

int main() {
  //freopen(PROBLEM_ID".in", "r", stdin);
  int n;
  cin >> n;
  vi a(n);
  for (int i = 0; i < n; ++i) {
    cin >> a[i];
  }
  if (n == 1) {
    cout << "YES" << endl;
    return 0;
  }
  ll sum = 0;
  for (int i = 0; i < a.size(); ++i) {
    sum += a[i];
  }
  if (sum % (ll(n) * ll(n + 1) / 2) != 0) {
    cout << "NO" << endl;
    return 0;
  }
  ll s = sum / (ll(n) * ll(n + 1) / 2);
  reverse(a.begin(), a.end());
  for (int i = 0; i < n; ++i) {
    int right = s - a[i] + a[(i + 1) % n];
    if (right < 0 || right % n != 0) {
      cout << "NO" << endl;
      return 0;
    }
  }
  cout << "YES" << endl;
  return 0;
}

Submission Info

Judge Result