View Code of Problem 27

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