Submission #1373045

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Source Code Expand

#include <map>
#include <set>
#include <list>
#include <cmath>
#include <ctime>
#include <deque>
#include <queue>
#include <stack>
#include <string>
#include <bitset>
#include <cstdio>
#include <limits>
#include <vector>
#include <climits>
#include <cstring>
#include <cstdlib>
#include <fstream>
#include <numeric>
#include <sstream>
#include <cassert>
#include <iomanip>
#include <iostream>
#include <algorithm>
#include <unordered_set>
#include <unordered_map>

using namespace std;

#define f first
#define s second
#define pb push_back
#define pp pop_back
#define mp make_pair
#define ll long long
#define ld double
#define ull unsigned long long
#define PI pair < int, int > 

const int N = 5e5 + 123;
const int M = 123;
const ld Pi = acos(-1);
const ll Inf = 1e18;
const int inf = 1e9;
const int mod = 1e9 + 7;
const int Sz = 501;
const int MOD = 1e9 + 7;

void add(int &a, int b) {
  a += b;
  if (a >= mod) a -= mod;
}
int mult(int a, int b) {
  return 1ll * a * b % mod;
}
int sum(int a, int b) {
  add(a, b);
  return a;
}

int n, a[N];

void solve() { 
  cin >> n;
  ll up = 0, dw = 0;
  for (int i = 1;i <= n;i++) {
    cin >> a[i];
    up += a[i];
    dw += i;
  }
  if (up % dw) {
    cout << "NO\n";
    return;
  }
  up /= dw;
  for (int i = 1;i <= n;i++) {
    int j = (i == 1 ? n : i - 1);
    int now = a[i] - a[j];
    if ((up - now) % n) {
      cout << "NO\n";
      return;
    }
  }
  cout << "YES\n";
}

int main() {
  #ifdef wws
   freopen("in", "r", stdin);
   // freopen("in", "w", stdout);
  #endif 
  ios_base::sync_with_stdio(0);
  int tt = 1; 
  while(tt--) solve();
  return 0;
}

Submission Info

Judge Result