@[difficultlong](/user/1435692) 判断质数可以优化，到 $\sqrt{n}$ 就行了。
by yanyan2 @ 2024-09-20 21:11:40
@[yanyan2](/user/1087963) 感谢，已关注(⊙o⊙)…！
by difficultlong @ 2024-09-20 21:16:18
```c++
#include<bits/stdc++.h>
using namespace std;
int sum,number,l;
bool Prime(int x){
for(int i=2;i*i<=n;i++){
if(!(x%i))return false;
return true;
}
int main(){
scanf("%d",&l);
int i=2;
while(sum<=l){
if(Prime(i)){
sum+=i;
number++;
printf("%d\n",i);
}
i++;
}
printf("%d",number);
return 0;
}
```
by congyuhan_yyds @ 2024-09-20 21:17:21