#include<bits/stdc++.h>
using namespace std;
int n,t,v[35005];
long long sol,s;
int main()
{
    freopen("euro.in","r",stdin);
    freopen("euro.out","w",stdout);
    scanf("%d%d",&n,&t);
    for(int i=1;i<=n;i++)
    {
        scanf("%d",&v[i]);
    }
    int i=1;
    while(i<n)
    {
        s+=1LL*v[i];
        if(s<0)
        {
            sol=sol+1LL*(s*i-t);
            s=0LL;
        }
        i++;
    }
    s+=1LL*v[i];
    sol=sol+1LL*(s*n-t);
    printf("%lld\n",sol);
    return 0;
}