9461번 - 탑다운 DP

[illuminoplanet]

#include <bits/stdc++.h>
#define endl '\n'
using namespace std;

typedef long long ll;
typedef pair<int, int> pii;

ll cache[101];

//D[N] = D[N-1] + D[N-5]
ll padovan(int n)
{
    ll& c = cache[n];
    if (c != -1) return c;
    if (n <= 3) return 1;
    if (n == 4 || n == 5) return 2;
    ///////////////////////////////////////////////
    return c = padovan(n-1)+padovan(n-5);
}

int main(void)
{
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);

    memset(cache, -1, sizeof(cache));

    int T; cin >> T;
    while (T--)
    {
        int n; cin >> n;
        cout << padovan(n) << endl;
    }

    return 0;
}