#include<stdio.h> int main() { int m,n; int i,k; int flag=0; int s; int y; scanf("%d %d",&m,&n); for(i=m;i<=n;i++) { s=i; y=0; while(s>0) { y=y*10+s%10; s=s/10; } //是回文,检查是不是素数 if(y==i) { for(k=2;k<=i/2;k++) { if(i%k==0) break; } if(k>=i/2) { flag++; printf("%6d",i); if(flag%5==0) printf("\n"); } } } return 0; } |
Double click to view unformatted code.