#include<bits/stdc++.h>
#define ll long long
#define el '\n'
#define all(a) a.begin(),a.end()

#include<ext/pb_ds/assoc_container.hpp>
#include<ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;
template<typename T>

using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
const ll N=1e5+5,mod=1e9+7;


void solve(ll t) {
    int n,m;
    cin>>n>>m;
    int p=m;
    int sol=0;
    while(n--){
        string s;
        cin>>s;
        int k;
         if(s.size()==1)
             k=s[0]-'0';
         else
             k=s[0]-'0'+1;
         if(k>m){
             sol++;
             m=p;
         }
         m-=k;
    }
    cout<<sol<<el;
}
int main() {
    ios_base::sync_with_stdio(0),cin.tie(0),cout.tie(0);

    ll t;
    //cin >> t;
    t = 1;
    for (ll i = 0 ; i < t ; i ++)
    {
        solve(t);
    }
}