#include<iostream> using namespace std; int main(){ int n,a,c=0,g,s,b,q; cin>>n; for(int i=1;i<=n;i++){ cin>>a; g=a/1%10; s=a/10%10; b=a/100%10; q=a/1000%10; if(g-q-b-s>0) c++; } cout<<c; return 0; }