Nothing is printing k-ordered LCS question

#1

I was going through the k-ordered LCS video. I understood the code. Wrote it on my own. Cross checked every line but still I am not getting any output. There is no syntax error. I tried debugging printing at different point. But nothing is printing. Is it possible my laptop cannot compute for so many case or the stack size is way too large as i am using top down dp. I have a mac 8GB ram, 64 bit processor, 256 SSD. i5 generation.

#include <bits/stdc++.h>

using namespace std;

int a[100], b[100];
long long dp[100][100][100];
int M, N;

long long k_lcs(int i, int j, int k) {
  long long res = 0;
  if (i >= N || j >= M)
    return 0;
  if (dp[i][j][k] != -1)
    return dp[i][j][k];
  if (a[i] == b[j])
    res = 1 + k_lcs(i + 1, j + 1, k);
  else {
    if (k > 0)
      res = 1 + k_lcs(i + 1, j + 1, k - 1);
    res = max(res, k_lcs(i + 1, j, k));
    res = max(res, k_lcs(i, j + 1, k));
  }
  res = dp[i][j][k];
  cout << dp[i][j][k] << endl;
  return res;
}

int main() {
  int k;
  cin >> M >> N >> k;
  memset(dp, -1, sizeof(dp));
  for (int i = 0; i < M; i++)
    cin >> a[i];
  for (int j = 0; k < N; j++)
    cin >> b[j];
  long long ans = k_lcs(0, 0, k);
  cout << ans;
  return 0;
}
#2

Hey Tanmay ! you made some mistakes while taking input in array b( constraint will be j but you have written k instead of j). and one moore thing if you want to use memoisation technique then you have to save res in dp[i][j][k] in every recursive call which you are doing oppositely , Other parts of your code is pretty good , just need to correct these mistakes. Fine now??