View Code of Problem 103

#include<iostream>
#include<cstring>
#include<string>
#include<algorithm>
#include<vector>
#include<math.h>
#include<map>
#include<typeinfo>
using namespace std;

bool fu(int num) {
	for (int i = 2; i*i <= num; i++) {
		if (num%i == 0) {
			return false;
		}
		
	}
	return true;
}
int main(){
	int a, b;
	int sum=0;
	cin >> a >> b;
	for (int i = a; i <= b; i++) {
		if (fu(i)) {
			sum++;
		}
	}
	cout << sum;
}