#include <bits/stdc++.h>
using namespace std;
#define int long long
void solve(){
int n,k;
cin>>n>>k;
vector<int>biber(n+1);
for(int i=1;i<=n;i++)cin>>biber[i];
/*for(int i=1;i<n;i++){int x,y;cin>>x>>y;biber[x].push_back(y);biber[y].push_back(x);}*/
int pre[n+1];
pre[0]=0;
for(int i=1;i<=n;i++)pre[i]=pre[i-1]+biber[i];
int ans=0;
int last=0;
for(int i=1;i<n;i++){
if(last+biber[i]>k){
ans++;
last=0;
}
last+=biber[i];
}
cout<<ans;
}
signed main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int t=1;
while(t--)solve();
}
