View Code of Problem 27

#include <stdio.h>
int main(){
	int a,b;
	while(scanf("%d%d",&a,&b)!=EOF){
		int i,j,sum=0;
		for(i=a+1;i<b;i++){
			int isPrime=1;
			for(j=2;j*j<=i;j++){
				if(i%j==0){
					isPrime=0;
					break;
				}
			}
			if(isPrime==1){
				sum+=i;
			}
		}
		printf("%d\n",sum);
	}
	return 0;
}