Submission #1163768

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Source Code Expand

#define _CRT_SECURE_NO_WARNINGS
#define _USE_MATH_DEFINES
 
#include "bits/stdc++.h"
using namespace std;
#define rep(i,n) for(int i=0;i<(n);++i)
#define rep2(i,a,b) for(int i=(a);i<(b);++i)
#define rrep(i,n) for(int i=(n)-1;i>=0;--i)
#define rrep2(i,a,b) for(int i=(a)-1;i>=b;--i)
#define range(i,a,b,c) for(int i=a;\
                    c>0?i<b:\
                    i>b;\
                    i+=c)
#define chmax(a, b) (a = (a) < (b) ? (b) : (a))
#define chmin(a, b) (a = (a) > (b) ? (b) : (a))
using ll = long long;
using ull = unsigned long long;
using ld = long double;
#define all(a) begin(a),end(a)
#define ifnot(a) if(not (a))
#define dump(x)  cerr << #x << " = " << (x) << endl
#define int long long
#ifdef _MSC_VER
const bool test = true;
#else 
const bool test = false;
#endif
 
int dx[] = { 1,0,-1,0 };
int dy[] = { 0,1,0,-1 };
const int INF = 1 << 28;
const ll INFL = (ll)1 << 58;
ll mod_n = (int)1e9 + 7;
const double eps = 1e-10;
typedef long double Real;
// return -1, 0, 1
int sgn(const Real& r) { return (r > eps) - (r < -eps); }
int sgn(const Real& a, const Real &b) { return sgn(a - b); }
 
//.....................
const int MAX = (int)2e5 + 5;
 
vector<string> split(const string &str, char sep) {
	vector<string> v;
	stringstream ss(str);
	string buffer;
	while (getline(ss, buffer, sep)) {
		v.push_back(buffer);
	}
	return v;
}
 
template<class InputIterator>
int sum(InputIterator begin, InputIterator end) {
	return accumulate(begin, end, 0ll);
}

int n;
vector<int> a;
int e[MAX];

bool ok() {
	int k = sum(all(a)) / (n*(n+1)/2);
	rep(i, n-1) {
		e[i] = a[(i+1)%n] - a[i] - k;
		if (e[i] == 0) continue;
		if (e[i] > 0) return false;
		if (abs(e[i]) % n != 0) return false;
	}
	return true;
}

void solve() {
	cin >> n;
	a.resize(n);
	rep(i, n) cin >> a[i];
	puts(ok() ? "YES" : "NO");
}

signed main() {
	cout << fixed << setprecision(20);
	while(true) {
		char s[MAX];
		if (scanf("%s", s) == EOF) break;
		int n = strlen(s);
		for (int i = n - 1; i > -1; i--) {
			ungetc(s[i], stdin);
		}
		solve();
	}
	return 0;
}

Submission Info

Judge Result