refactor: 0077.组合.md

problems/0077.组合.md

@@ -469,6 +469,32 @@ func dfs(n int, k int, start int) {
 ```
 
 ### Javascript
+未剪枝：
+
+```js
+var combine = function (n, k) {
+  // 回溯法
+  let result = [],
+    path = [];
+  let backtracking = (_n, _k, startIndex) => {
+    // 终止条件
+    if (path.length === _k) {
+      result.push(path.slice());
+      return;
+    }
+    // 循环本层集合元素
+    for (let i = startIndex; i <= _n; i++) {
+      path.push(i);
+      //   递归
+      backtracking(_n, _k, i + 1);
+      //   回溯操作
+      path.pop();
+    }
+  };
+  backtracking(n, k, 1);
+  return result;
+};
+```
 
 剪枝：