#include<bits/stdc++.h>
using namespace std;
vector<int>vec1;
vector<int>vec2;

int main(){
	int a,i;
	i = 0;
	while(cin>>a){
		if(i >= 10)break;
		vec1.push_back(a);
		i = i + 1;
	}
	i = a + 30;
	for(int ii =0;ii <= vec1.size();ii++){
		if(vec1[ii] <= i){
			vec2.push_back(vec1[ii]);
		}
	}
	cout<<vec2.size();
	return 0;
}