CodeForces C

#include <iostream>
#include <algorithm>

using namespace std;

bool comparator(int a, int b) {
    return (a % 10) > (b % 10);
}

int main() {

    int n, k;
    cin >> n >> k;
    int* a = new int[n];
    for (int i = 0; i < n; i++) {
        cin >> a[i];
    }

    sort(a, a + n, comparator);

    for (int i = 0; i < n; i++) {
        int tmp = a[i] % 10;
        if (tmp != 0) {
            if (k > (10 - tmp)) {
                a[i] += (10 - tmp);
                k -= (10 - tmp);
            } else {
                a[i] += k;
                k = 0;
                break;
            }
        } else {
            a[i] += (k % 10);
            break;
        }
    }

    int val = 0;
    for (int i = 0; i < n; i++) {
        val += (a[i] / 10);
    }

    cout << val;
}