I - Matrix Sum

#include <bits/stdc++.h>
#define pb push_back
#define mk make_pair
#define fi first
#define se second
#define For(i,a,b) for(int (i)=(a);(i) < (b); ++(i))
using namespace std;
typedef vector<int> vi;
typedef pair<int,int> ii;
typedef long long ll;
typedef vector<bool> vb;
const int N=1010;

ll sm, s, n, r[N], c[N], m[N][N], a[N][N];

int main(void) {
    cin >> n;
    For(i,0,n)
        For(j,0,n) {
            cin >> m[i][j];
            c[j]+=m[i][j];
            r[i]+=m[i][j];
            sm += m[i][j];
        }

    if (n == 1) {
        if (m[0][0] == 0 || m[0][0] == 1)
            goto ans_1;
        goto ans_0;
    }

    if (sm % (2*n - 1) != 0)
        goto ans_0;

    s = sm / (ll)(2*n-1);

    for (int i = 0; i<n; i++)
        for (int j = 0; j<n; j++) {
            if ((c[j]-s)%(n-1) != 0)
                goto ans_0;

            ll sa = (c[j]-s)/(n-1);

            if ((r[i]-s)%(n-1) != 0)
                goto ans_0;

            ll sb = (r[i]-s)/(n-1);

            a[i][j] = sa + sb - m[i][j];
            if (a[i][j] > 1 || a[i][j] < 0)
                goto ans_0;
        }

ans_1:
    cout << "1\n";
    return 0;

ans_0:
    cout << "0\n";
    return 0;
}