#include <vector>
#include <cstdio>
using namespace std;
int main() {
    int n;
    if (!(cin >> n)) return 0;
    vector<long long> count(7, 0);
    count[0] = 1;
    long long current_sum = 0;
    long long result = 0;

    for (int i = 0; i < n; ++i) {
        int num;
        cin>>num; 
        current_sum += num;
        int rem = (current_sum % 7 + 7) % 7;
        result += count[rem];
        count[rem]++;
    }

    cout << result << endl;

    return 0;
}```