usaco subsequence summing to seven

//Bismillahir Rahman-ir Rahim
#include <bits/stdc++.h>
using namespace std;
#define debug(x) cout << '>' << #x << " : " << x << endl;
#define all(c) c.begin(), c.end()
#define F first
#define S second
typedef unsigned long long ull;
typedef long long ll;


int main(){

    //freopen("input.txt", "r", stdin);
    //freopen("output.txt", "w", stdout);

    long long int n;
    cin >> n;
    vector <long long> ara(n), pre(n);
    for(int i = 0;i < n; i++){
        cin >> ara[i];
    }
    pre[0] = ara[0];
    for(int i = 1; i < n; i++){
        pre[i] = pre[i-1] + ara[i];
    }
    ll ans = 0, sum = 0;
    for(int i = 0; i < n; i++){
        for(int j = i; j < n; j++){
            if(i!=0)sum = pre[j] - pre[i-1];
            else sum = pre[j];
            if(sum % 7 == 0){
                ans = max(ans, (ll)(j-i+1));
            }
        }
    }
    cout << ans << endl;
}