add: 返回给定数组的所有排列

dengshasha · Feb 4, 2022 · 9cfa834 · 9cfa834
1 parent 95c6261
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diff --git a/README.md b/README.md
@@ -88,6 +88,8 @@
 17. [容器最大面积](https://github.com/dengshasha/algorithm-study/blob/master/array/containerWithMostWater.js) || [leetcode地址](https://leetcode.com/problems/container-with-most-water/submissions/)
 18. [寻找数组中满足大于左右邻居的一个数](https://github.com/dengshasha/algorithm-study/blob/master/array/findPeakElement.js) || [leetcode地址](https://leetcode.com/problems/find-peak-element/)
 19. [返回数组中每个元素向右到边界，比该元素小的元素的总数](https://github.com/dengshasha/algorithm-study/blob/master/array/countSmaller.js) || [leetcode地址](https://leetcode.com/problems/count-of-smaller-numbers-after-self/submissions/)
+20. [返回给定数组的所有排列](https://github.com/dengshasha/algorithm-study/blob/master/array/permutations.js) || [leetcode地址](https://leetcode.com/problems/permutations/submissions/)
+21. [返回给定数组(含重复元素)的所有排列](https://github.com/dengshasha/algorithm-study/blob/master/array/permutationsII.js) || [leetcode地址](https://leetcode.com/problems/permutations-ii/submissions/)
 
 ### 动态规划
 1. [强盗偷东西，价值最大化](https://github.com/dengshasha/algorithm-study/blob/master/dynamicProgramming/houseRobber.js) || [leetcode地址](https://leetcode.com/problems/house-robber/)

diff --git a/array/permutations.js b/array/permutations.js
@@ -0,0 +1,29 @@
+/**
+ * @param {number[]} nums
+ * @return {number[][]}
+ */
+var permute = function(nums) {
+    let res = []
+    function recursion(l, r) {
+        if(l===r) {
+            res.push(nums.slice(0))
+            return;
+        }
+        for(let i = l; i <= r; i++) {
+            swap(i,l,nums)
+            recursion(l+1, r)
+            swap(i,l,nums)
+        }
+    }
+    recursion(0, nums.length-1)
+    return res;
+};
+
+function swap(i, j, nums) {
+    let temp = nums[i]
+    nums[i] = nums[j]
+    nums[j] = temp
+    return nums;
+}
+
+console.log(permute([1,2,3]))
diff --git a/array/permutationsII.js b/array/permutationsII.js
@@ -0,0 +1,34 @@
+/**
+ * @param {number[]} nums
+ * @return {number[][]}
+ * leetcode address: https://leetcode.com/problems/permutations-ii/
+ */
+var permuteUnique = function(nums) {
+    let res = []
+    function recursion(l, r) {
+        if(l===r) {
+            res.push(nums.slice(0))
+            return;
+        }
+        let obj = {}
+        for(let i = l; i <= r; i++) {
+            if(!obj[nums[i]]) {
+                swap(i,l,nums)
+                recursion(l+1, r)
+                swap(i,l,nums)
+                obj[nums[i]] = 1
+            }
+        }
+    }
+    recursion(0, nums.length-1)
+    return res;
+};
+
+function swap(i, j, nums) {
+    let temp = nums[i]
+    nums[i] = nums[j]
+    nums[j] = temp
+    return nums;
+}
+
+console.log(permuteUnique([2,2,1,1]))
diff --git a/index.html b/index.html
@@ -6,6 +6,6 @@
     <title>Document</title>
 </head>
 <body>
-    <script src="string/regExpMatch.js"></script>
+    <script src="array/permutationsII.js"></script>
 </body>
 </html>