https://leetcode.cn/problems/unique-paths-ii

Author: masx200

README.md

@@ -10,6 +10,8 @@ leetcode 测试
 
 ##### 包含的内容如下
 
+https://leetcode.cn/problems/unique-paths-ii
+
 https://leetcode.cn/problems/rectangle-overlap/
 
 https://leetcode.cn/problems/design-an-expression-tree-with-evaluate-function/

unique-paths-ii/index.ts

@@ -0,0 +1,20 @@
+function uniquePathsWithObstacles(obstacleGrid: number[][]): number {
+    if (obstacleGrid[0][0] === 1) return 0;
+    const m = obstacleGrid.length,
+        n = obstacleGrid[0].length;
+    if (obstacleGrid[m - 1][n - 1] === 1) return 0;
+
+    const f: number[] = Array(n).fill(0);
+    f[0] = 1;
+    for (let i = 0; i < m; i++) {
+        for (let j = 0; j < n; j++) {
+            if (obstacleGrid[i][j] === 1) {
+                f[j] = 0;
+            } else if (j >= 1 && obstacleGrid[i][j - 1] === 0) {
+                f[j] = f[j] + f[j - 1];
+            }
+        }
+    }
+    return f[f.length - 1];
+}
+export default uniquePathsWithObstacles;