Câu trả lời:
#include<bits/stdc++.h>
using namespace std;
int main(){
//freopen("dayso.inp","r",stdin);
//freopen("dayso.out","w",stdout);
int n,k;
cin>>n>>k;
int d,a;
int dem=0;
for (int i=1;i<=n;i++){cin >> a>>d;
if ((k-a)%d==0){dem++;}
}
cout<<dem;
}