xuzihao123 @ 2023-07-21 09:19:32
#include <iostream>
#include <sstream>
#include <cstdlib>
#include <ctime>
using namespace std;
int gu(int i){
string s;
stringstream ss;
ss<<i;
ss>>s;
int l,r;
l=0;
r=s.size()-1;
while(l<r){
if(s[l]!=s[r])return 0;
l++;
r--;
}
return 1;
}
int su(int i){
if(i==0||i==1)return 0;
if(i==2)return 1;
for(int k=2;k*k<=i;k++)if(i%k==0)return 0;
return 1;
}
int main(){
int l,r;
int a,b;
cin>>a>>b;
for(int i=a;i<=b;i++){
if(i%2==0)continue;
if(gu(i))if(su(i))cout<<i<<endl;
}
}by lijuncheng_1207 @ 2023-07-27 17:59:11
@xuzihao123 我与你一样
#include <bits/stdc++.h>
using namespace std;
int n,m,cnt;
bool prime(int x){
for(int i=2;i<=sqrt(x);i++) {
if(x%i==0)
return 0;
}
return 1;
}
bool flag(int x){
string s=to_string(x);
string s1=s;
reverse(s.begin(),s.end());
if(s1==s){
return 1;
}
return 0;
}
int main(){
std::ios::sync_with_stdio(false);
std::cin.tie(0),cout.tie(0);
cin>>n>>m;
for(int i=n;i<=m;i++) {
if(prime(i)&&flag(i)){
cout<<i<<endl;
}
}
return 0;
}