/* -*- coding: utf-8 -*-
 *
 * 3654.cc:  No.3654 Cup Ramen - yukicoder
 */

#include<cstdio>
#include<algorithm>

using namespace std;

/* main */

int main() {
  int n, x;
  scanf("%d%d", &n, &x);
  int sum = 0;
  for (int i = 0; i < n; i++) {
    int ai;
    scanf("%d", &ai);
    sum += ai;
  }

  printf("%d\n", max(0, sum - x));
  
  return 0;
}