1 class Solution { 2     public int uniquePaths(int m, int n) { 3         int[][] res = new int[m][n]; 4         if(m == 0 || n == 0) return 0; 5         res[0][0] = 1; 6         for(int i = 0; i < m; i++) { 7             for(int j = 0; j < n; j++) { 8                 if(i == 0 && j ==0) continue; 9                 if(i - 1 < 0) {10                     res[i][j] = res[i][j - 1];11                 }else if(j - 1 < 0) {12                     res[i][j] = res[i - 1][j];13                 }else {14                     res[i][j] = res[i - 1][j] + res[i][j - 1];15                 }16                 17             }18         }19         return res[m - 1][n - 1];20     }21 }

没啥特别的