1077

include <iostream>
using namespace std; 
int main() {
    int n,b,c,ge,shi,bai,qian;
    cin>>n;
    int a[n];
    for(int i = 0;i<n;i++){
        cin>>b;
        ge = b%1000%100%10;
        shi = b%1000%100/10;
        bai = b%1000/100;
        qian = b/1000;
        if(ge-qian-bai-shi>0){
            c++;
        }
    }
    cout<<c;
    return 0;    
}