#include<bits/stdc++.h> using namespace std; int main(){ int n,a,s=0,ge,shi,bai,qian; cin>>n; for(int i=1;i<=n;i++){ cin>>a; ge=a%10; shi=a/10%10; bai=a/100%10; qian=a/1000; if(ge-qian-bai-shi>0) s++; } cout<<s; return 0; }