문제
풀이
#include <iostream>
#include <vector>
using namespace std;
int n;
vector<int> dp(31, 0);
void solve(void) {
dp[0] = 1;
for (int i=2; i<=30; i+=2) {
dp[i] = dp[i-2] * 3;
for (int j=i-4; j>=0; j-=2) {
dp[i] += dp[j] * 2;
}
}
cin >> n;
cout << dp[n];
}
int main(void) {
ios::sync_with_stdio(false);
cin.tie(nullptr);
solve();
return 0;
}