Code:

#include <bits/stdc++.h>
#define int long long
using namespace std;
const int MAXN = 1e5 + 100;
int n, m, all, sz = INT_MAX, a[MAXN];
signed main(){
	cin >> n >> m;
	for(int i = 0; i < n; i++){
		cin >> a[i];
	}
	sort(a, a + n);
	n--;
	for(int i = 1; i <= n; i++){
		sz = min(sz, a[i]);
	}
	sz++;
	while(1){
		if(m < 1) break;
		bool flag = 0;
		for(int i = 1; i <= n; i++){
			if(a[i] < sz && m >= 1){
				flag = 1;
				a[i]++;
				m--;
			}
		}
		if(flag == 0) sz++;
	}
	sort(a + 1, a + n + 1);
	for(int i = 1; i < n; i++){
		all += a[i];
	}
	cout << all << endl;
	return 0;
}