ok

NoteXYX · NoteXYX · commit bbb72e6b9e54 · 2020-08-24T09:18:00.000+08:00
diff --git a/src/com/leetcode/Main77.java b/src/com/leetcode/Main77.java
@@ -0,0 +1,31 @@
+package com.leetcode;
+
+import java.util.LinkedList;
+import java.util.List;
+
+public class Main77 {
+    public List<List<Integer>> res = new LinkedList<>();
+    public void cur(LinkedList<Integer> curr, int n ,int k, int first) {
+        if (curr.size() == k) {
+            res.add(new LinkedList<>(curr));
+            return;
+        }
+        for (int i = first; i <= n; i++) {
+            curr.add(i);
+            cur(curr, n, k, i + 1);
+            curr.removeLast();
+        }
+    }
+    public List<List<Integer>> combine(int n, int k) {
+        LinkedList<Integer> cur = new LinkedList<>();
+        cur(cur, n, k, 1);
+        return res;
+    }
+
+    public static void main(String[] args) {
+        int n = 4;
+        int k = 2;
+        Main77 m = new Main77();
+        System.out.println(m.combine(n, k));
+    }
+}
