规范格式

leetcode/0063.Unique-Paths-II/63. Unique Paths II.go

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+package leetcode
+
+func uniquePathsWithObstacles(obstacleGrid [][]int) int {
+	if len(obstacleGrid) == 0 || obstacleGrid[0][0] == 1 {
+		return 0
+	}
+	m, n := len(obstacleGrid), len(obstacleGrid[0])
+	dp := make([][]int, m)
+	for i := 0; i < m; i++ {
+		dp[i] = make([]int, n)
+	}
+	dp[0][0] = 1
+	for i := 1; i < n; i++ {
+		if dp[0][i-1] != 0 && obstacleGrid[0][i] != 1 {
+			dp[0][i] = 1
+		}
+	}
+	for i := 1; i < m; i++ {
+		if dp[i-1][0] != 0 && obstacleGrid[i][0] != 1 {
+			dp[i][0] = 1
+		}
+	}
+	for i := 1; i < m; i++ {
+		for j := 1; j < n; j++ {
+			if obstacleGrid[i][j] != 1 {
+				dp[i][j] = dp[i-1][j] + dp[i][j-1]
+			}
+		}
+	}
+	return dp[m-1][n-1]
+}

leetcode/0063.Unique-Paths-II/63. Unique Paths II_test.go

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+package leetcode
+
+import (
+	"fmt"
+	"testing"
+)
+
+type question63 struct {
+	para63
+	ans63
+}
+
+// para 是参数
+// one 代表第一个参数
+type para63 struct {
+	og [][]int
+}
+
+// ans 是答案
+// one 代表第一个答案
+type ans63 struct {
+	one int
+}
+
+func Test_Problem63(t *testing.T) {
+
+	qs := []question63{
+
+		question63{
+			para63{[][]int{
+				[]int{0, 0, 0},
+				[]int{0, 1, 0},
+				[]int{0, 0, 0},
+			}},
+			ans63{2},
+		},
+
+		question63{
+			para63{[][]int{
+				[]int{0, 0},
+				[]int{1, 1},
+				[]int{0, 0},
+			}},
+			ans63{0},
+		},
+
+		question63{
+			para63{[][]int{
+				[]int{0, 1, 0, 0},
+				[]int{1, 0, 0, 0},
+				[]int{0, 0, 0, 0},
+			}},
+			ans63{0},
+		},
+	}
+
+	fmt.Printf("------------------------Leetcode Problem 63------------------------\n")
+
+	for _, q := range qs {
+		_, p := q.ans63, q.para63
+		fmt.Printf("【input】:%v       【output】:%v\n", p, uniquePathsWithObstacles(p.og))
+	}
+	fmt.Printf("\n\n\n")
+}

leetcode/0063.Unique-Paths-II/README.md

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+# [63. Unique Paths II](https://leetcode.com/problems/unique-paths-ii/)
+
+
+## 题目
+
+A robot is located at the top-left corner of a *m* x *n* grid (marked 'Start' in the diagram below).
+
+The robot can only move either down or right at any point in time. The robot is trying to reach the bottom-right corner of the grid (marked 'Finish' in the diagram below).
+
+Now consider if some obstacles are added to the grids. How many unique paths would there be?
+
+![](https://assets.leetcode.com/uploads/2018/10/22/robot_maze.png)
+
+An obstacle and empty space is marked as `1` and `0` respectively in the grid.
+
+**Note:** *m* and *n* will be at most 100.
+
+**Example 1:**
+
+    Input:
+    [
+      [0,0,0],
+      [0,1,0],
+      [0,0,0]
+    ]
+    Output: 2
+    Explanation:
+    There is one obstacle in the middle of the 3x3 grid above.
+    There are two ways to reach the bottom-right corner:
+    1. Right -> Right -> Down -> Down
+    2. Down -> Down -> Right -> Right
+
+## 题目大意
+
+一个机器人位于一个 m x n 网格的左上角 （起始点在下图中标记为“Start” ）。机器人每次只能向下或者向右移动一步。机器人试图达到网格的右下角（在下图中标记为“Finish”）。现在考虑网格中有障碍物。那么从左上角到右下角将会有多少条不同的路径？
+
+
+## 解题思路
+
+- 这一题是第 62 题的加强版。也是一道考察 DP 的简单题。
+- 这一题比第 62 题增加的条件是地图中会出现障碍物，障碍物的处理方法是 `dp[i][j]=0`。
+- 需要注意的一种情况是，起点就是障碍物，那么这种情况直接输出 0 。