USACO Cow Pedigrees

/*
ID: david.h2
LANG: C++11
TASK: nocows
*/

#include <iostream>
#include <vector>

using namespace std;

vector<vector<int>> results(201, vector<int>(101, -1));

int findntrees(int n, int k) {
    if (n == 0){
        results[n][k] = 1;
    } else if (k == 0) {
        results[n][k] = 0;
    } else if (results[n][k] == -1) {
        int childpossibilities = 0;
        for (int leftnodes = 0; leftnodes <= n - 2; leftnodes+=2) {
            int rleft = findntrees(leftnodes, k - 1);
            int rright = findntrees(n - 2 - leftnodes, k - 1);
            childpossibilities += rleft * rright;
            childpossibilities %= 9901;
        }
        results[n][k] = childpossibilities % 9901;
    }
    return results[n][k] % 9901;
}

int main() {
    FILE *fin = fopen("nocows.in", "r");
    FILE *fout = fopen("nocows.out", "w");
    int n, k;
    fscanf(fin, "%d %d", &n, &k);
    if (n % 2 == 0) {
        fprintf(fout, "%d\n", 0);
        return 0;
    }
    n -= 1;
    k -= 1;
    fprintf(fout, "%d\n", ((findntrees(n, k) + 9901) - findntrees(n, k - 1)) % 9901);
    return 0;
}