#include<iostream> #include<algorithm> using namespace std; bool isHuiwen(int i){ string s1=to_string(i); string s2=s1; reverse(s1.begin(),s1.end()); if(s1==s2){ return true; } else { return false; } } bool isPrime(int n){ if(n<=1){ return false; } else if(n==2){ return true; } else { for(int i=2;i*i<=n;++i){ if(n%i==0){ return false; } } return true; } } int main(){ int m; int n; cin>>m>>n; int count=0; for(int i=m;i<=n;++i){ if(isHuiwen(i) && isPrime(i)){ count++; if(count%5!=1){ printf(" "); } printf("% 6d",i); if(count%5==0 && count!=0){ printf("\n"); } } } return 0; } |
Double click to view unformatted code.