Merge branch 'master' of github.com:youngyangyang04/leetcode-master

Author: youngyangyang04

problems/0063.不同路径II.md

@@ -176,16 +176,14 @@ class Solution {
     public int uniquePathsWithObstacles(int[][] obstacleGrid) {
         int n = obstacleGrid.length, m = obstacleGrid[0].length;
         int[][] dp = new int[n][m];
-        dp[0][0] = 1 - obstacleGrid[0][0];
-        for (int i = 1; i < m; i++) {
-            if (obstacleGrid[0][i] == 0 && dp[0][i - 1] == 1) {
-                dp[0][i] = 1;
-            }
+	
+        for (int i = 0; i < m; i++) {
+	    if (obstacleGrid[0][i] == 1) break; //一旦遇到障碍，后续都到不了
+	    dp[0][i] = 1;
         }
-        for (int i = 1; i < n; i++) {
-            if (obstacleGrid[i][0] == 0 && dp[i - 1][0] == 1) {
-                dp[i][0] = 1;
-            }
+        for (int i = 0; i < n; i++) {
+	    if (obstacleGrid[i][0] == 1) break; ////一旦遇到障碍，后续都到不了
+	    dp[i][0] = 1;
         }
         for (int i = 1; i < n; i++) {
             for (int j = 1; j < m; j++) {