Gleb And Pizza CodeForces - 842B

CodeForces - 842B

 #include<bits/stdc++.h>
 using namespace std;

 int main() {
     int r,d,t;
     double temp,x,y,z;
     while(~scanf("%d %d",&r,&d)) {
         scanf("%d",&t);
         int ans = ;
         for(int i = ; i < t; i++) {
             scanf("%lf %lf %lf",&x,&y,&z);
             temp = sqrt(x*x + y*y) - z ;
             if (temp >= (r-d) && temp + z + z <= r ) ans++;
          }
         cout<<ans<<endl;
     }
     return ;
 }