#include <bits/stdc++.h>
using namespace std;

bool comp(int a, int b) {
    return a > b;
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);

    long long n, k;
    cin >> n >> k;

    long long prices[200000];
    long long sum = 0;

    for(int i = 0; i < n; i++) {
        cin >> prices[i];
        sum += prices[i];
    }

    long long delta = n * k - sum;

    if (delta == 0) {
        cout << "0" << endl;
    }
    else if (delta > 0) {
        cout << "1" << endl;
    }
    else {
        sort(prices, prices + n, comp);

        int res = 0;
        int i = 0;

        while(delta != 0) {
            delta += min(prices[i] - 1, -delta);
            res++;
            i++;
        }

        cout << res << endl;
    }
}