#include <stdio.h> #include <math.h> int Issu(int n) { int i; if(n == 1 || n == 0) return 0; else { for(i = 2;i <= sqrt(n);i++) { if(n % i == 0) return 0; } return 1; } } int hw(int n) { int arr[5] = {0},i = 0,t = n,j,index = 1; while(t) { arr[i++] = t % 10; t /= 10; } for(j = 0;j < i / 2;j++) { if(arr[j] != arr[i - j - 1]) { index = 0; break; } } return index; } int main(void) { int min,max,i; while(scanf("%d%d",&min,&max) != EOF) { int index = 1; for(i = min;i <= max;i++) { if(hw(i) && Issu(i)) { if(index != 5) printf("%6d",i); else { printf("%6d\n",i); index = 0; } index++; } } } return 0; } |
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