#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <algorithm>
#include <vector>
#include <cmath>

using namespace std;

#define file_in "euro.in"
#define file_out "euro.out"

#define nmax 34569

int n,k;
int v[nmax];

void citire()
{
    freopen(file_in,"r",stdin);
    freopen(file_out,"w",stdout);

    scanf("%d %d", &n, &k);
    for (int i=1;i<=n;++i)
         scanf("%d", &v[i]);


}

void solve()
{
    long long suma,ans;
    int i;
     suma=0;
     ans=0;
     for (i=1;i<=n;++i)
     {
         suma+=v[i];
         if (suma<0)
         {
             ans+=(suma*i-k);
             //printf("%d\n", suma*i-k);
             suma=0;
         }
     }

     ans+=(suma*n-k);
      //printf("%d\n", suma*n-k);
     printf("%lld\n", ans);
}

int main()
{
    citire();
    solve();

    fclose(stdin);
    fclose(stdout);

    return 0;
}