#include "
stdio.h"
int prime(int n){//判断素数
int i;
if(n>2 && !(n&1) || n<2)
return 0;
for(i=3;i*i<=n;i+=2)
if(!(n%i))
return 0;
return 1;
}
int main(int argc,char *argv[]){
int n,m;
printf("Please enter n(int 0<n)...\nn=");
if(scanf("%d",&n)!=1 || n<1){
printf("Input error, exit...\n");
return 0;
}
printf("Between 1 and %d a total of ",n);
for(m=0;n>1;m+=prime(n--));
printf("%d prime.\n",m);
return 0;
}
运行样例:
![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/5243fbf2b2119313b2a19cac68380cd790238dcf?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)