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02023.cpp
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02023.cpp
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#include <iostream>
#include <cmath>
using namespace std;
int n;
bool prime(int num) {
if (num == 1) return false;
if (num == 2) return true;
if (num % 2 == 0) return false;
for (int i=3; i<=sqrt(num); i+=2) {
if (num % i == 0) return false;
}
return true;
}
void backtrack(int idx, int num) {
if (idx == n) {
if (prime(num)) cout << num << "\n";
return;
}
if (prime(num)) {
backtrack(idx+1, num*10+1);
backtrack(idx+1, num*10+3);
backtrack(idx+1, num*10+5);
backtrack(idx+1, num*10+7);
backtrack(idx+1, num*10+9);
}
}
void solve(void) {
cin >> n;
backtrack(1, 2);
backtrack(1, 3);
backtrack(1, 5);
backtrack(1, 7);
}
int main(void) {
ios::sync_with_stdio(false);
cin.tie(nullptr); cout.tie(nullptr);
solve();
return 0;
}