《Super Washing Machines》

#include<bits/stdc++.h>
using namespace std;
typedef long long LL;
typedef pair<int,int> pii;
const int N = 1e4 + 5;
const int M = 3e5 + 5;
const LL Mod = 1e9 + 7;
#define pi acos(-1)
#define INF 1e10
#define dbg(ax) cout << "now this num is " << ax << endl;
namespace FASTIO{
    inline LL read(){
        LL x = 0,f = 1;char c = getchar();
        while(c < '0' || c > '9'){if(c == '-') f = -1;c = getchar();}
        while(c >= '0' && c <= '9'){x = (x<<1)+(x<<3)+(c^48);c = getchar();}
        return x*f;
    }
}
using namespace FASTIO;

int a[N];
int main()
{
    int n;
    while(cin >> n){
        int sum = 0;
        for(int i = 1;i <= n;++i) a[i] = read(),sum += a[i];
        if(sum % n != 0) printf("-1\n");
        else{
            sum /= n;
            int mx = 0,move = 0;
            for(int i = 1;i <= n;++i){
                move += a[i] - sum;
                mx = max(mx,max(a[i] - sum,abs(move)));
            }
            printf("%d\n",mx);
        }
    }
    system("pause");
    return 0;
}