题解 | #不同路径的数目(一)#

    public static int uniquePaths (int m, int n) {
        int[][] dp = new int[m+1][n+1];
        for (int i = dp.length - 1; i >= 0; i--) {
            for (int j = dp[i].length - 1; j >= 0; j--) {
                if(i>=m||j>=n){
                    dp[i][j] = 0;
                }else if(i==m-1&&j==n-1){
                    dp[i][j] = 1;
                }else{
                    dp[i][j] = dp[i+1][j]+dp[i][j+1];
                }
            }
        }
        return dp[0][0];
    }