素数和

/*作者:QHY题目:p1462 素数和*/#include<iostream>#include<cstdio>#include<cstring>#include<cmath>using namespace std;int a,b,x,y;int  bl[70000];long long ans=0;int main(){memset(bl, 0, sizeof bl);cin>>a>>b;x=min(a,b);y=max(a,b);for(int i=2;i<y;i++){if(!bl[i]){if(i>x)ans+=i;for(int j=i;j<y;j+=i)bl[j]=1;}}cout<<ans;return 0;}