答案

#include <iostream>
using namespace std;
int main(){
	int n;
    cin >> n;
    for (int i = 1; i <= n; ++i) {
		int x = 0;
		int t = i;
		while(t > 0){
			x = x * 10 + t % 10;
			t = t / 10;
		}if(x == i){
			cout << i << endl;
		}
	}   
	return 0;
}