LeetCode 62. Unique Paths

public class Solution {    public int uniquePaths(int m, int n) {        int[][] paths = new int[m][n];        for (int i = 0; i < m; i++) {        for (int j = 0; j < n; j++) {        if (i == 0 || j == 0) paths[i][j] = 1;        else paths[i][j] = paths[i - 1][j] + paths[i][j - 1];        }        }        return paths[m - 1][n - 1];    }}