#include<stdio.h>
long long s1,s2,s;
int n,t,i;
int main()
{freopen("euro.in","r",stdin);
 freopen("euro.out","w",stdout);
 scanf("%d %d",&n,&t);
 for(i=1;i<n;i++)
 {scanf("%lld",&s2);
  s1=s1+s2;
  if(s1<0) {s=s+i*s1-t;s1=0;} }
 scanf("%lld",&s2);
 s1=s1+s2;
 s=s+n*s1-t;
 printf("%lld",(long long)s);
 return 0;}