leetcode62-不同路径

不同路径

• 图dp

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