Day 26 — Unique Paths

class Solution {
    public int uniquePaths(int m, int n) {
        if(m == 0 || n == 0) return 0;
        int[][] grid = new int[m][n];
        //fill all cells with 1. This will eventually be updated
        for(int[] ar: grid) {
            Arrays.fill(ar, 1);
        }
        
        for(int i = 1 ; i < m; i++){
            for(int j = 1 ; j < n ; j++) {
                grid[i][j] = grid[i-1][j] + grid [i][j-1];
            }
        }
        return grid[m-1][n-1];
    }
}