add 46.47.48.49.50. golang

Author: zj972

README.md

@@ -49,6 +49,10 @@
 |043|Multiply Strings|[Golang](https://github.com/zj972/leetcode/tree/master/code/043.%20Multiply%20Strings)|Medium|
 |044|Wildcard Matching|[Golang](https://github.com/zj972/leetcode/tree/master/code/044.%20Wildcard%20Matching)|Hard|
 |045|Jump Game II|[Golang](https://github.com/zj972/leetcode/tree/master/code/045.%20Jump%20Game%20II)|Hard|
+|046|Permutations|[Golang](https://github.com/zj972/leetcode/tree/master/code/046.%20Permutations)|Medium|
+|047|Permutations II|[Golang](https://github.com/zj972/leetcode/tree/master/code/047.%20Permutations%20II)|Medium|
+|048|Rotate Image|[Golang](https://github.com/zj972/leetcode/tree/master/code/048.%20Rotate%20Image)|Medium|
+|049|Group Anagrams|[Golang](https://github.com/zj972/leetcode/tree/master/code/049.%20Group%20Anagrams)|Medium|
 |058|Length of Last Word|[JavaScript](https://github.com/zj972/leetcode/tree/master/code/058.%20Length%20of%20Last%20Word)|Easy|
 |062|Unique Paths|[JavaScript](https://github.com/zj972/leetcode/tree/master/code/062.%20Unique%20Paths)|Medium|
 |066|Plus One|[JavaScript](https://github.com/zj972/leetcode/tree/master/code/066.%20Plus%20One)|Easy|

code/045. Jump Game II/main.go

@@ -30,27 +30,43 @@ import (
 //	return jumpFrom(0, nums, list)
 //}
 
+//Runtime: 12 ms, faster than 100.00% of Go online submissions for Jump Game II.
+//func jump(nums []int) int {
+//	n := len(nums)
+//	if n == 0 || n == 1 || nums[0] == 0 {
+//		return 0
+//	}
+//	start, end, jumps := 0, 0, 0
+//	for dest := 0; dest < n-1; {
+//		for i := start; i <= end; i++ {
+//			if dest < i+nums[i] {
+//				dest = i + nums[i]
+//			}
+//		}
+//		start = end + 1
+//		end = dest
+//		jumps++
+//	}
+//	return jumps
+//}
+
 //Runtime: 12 ms, faster than 100.00% of Go online submissions for Jump Game II.
 func jump(nums []int) int {
-	n := len(nums)
-	if n == 0 || n == 1 || nums[0] == 0 {
-		return 0
-	}
-	start, end, jumps := 0, 0, 0
-	for dest := 0; dest < n-1; {
-		for i := start; i <= end; i++ {
-			if dest < i+nums[i] {
-				dest = i + nums[i]
-			}
+	var ret, curMax, curRch int
+	for i := 0; i < len(nums); i++ {
+		fmt.Println(i, nums[i], curMax, curRch, ret)
+		if curRch < i {
+			ret++
+			curRch = curMax
+		}
+		if curMax < nums[i]+i {
+			curMax = nums[i] + i
 		}
-		start = end + 1
-		end = dest
-		jumps++
 	}
-	return jumps
+	return ret
 }
 
 func main() {
-	var data = []int{2, 3, 1, 1, 4}
+	var data = []int{4, 5, 2, 1, 3, 4, 5, 1, 6, 2, 1}
 	fmt.Println(jump(data))
 }

code/046. Permutations/README.md

@@ -0,0 +1,40 @@
+# 46. Permutations
+
+Given a collection of distinct integers, return all possible permutations.
+
+##### Example:
+
+Input: [1,2,3]
+
+Output:
+
+```text
+[
+  [1,2,3],
+  [1,3,2],
+  [2,1,3],
+  [2,3,1],
+  [3,1,2],
+  [3,2,1]
+]
+```
+
+
+给定一个没有重复数字的序列，返回其所有可能的全排列。
+
+##### 示例:
+
+输入: [1,2,3]
+
+输出:
+
+```text
+[
+  [1,2,3],
+  [1,3,2],
+  [2,1,3],
+  [2,3,1],
+  [3,1,2],
+  [3,2,1]
+]
+```

code/046. Permutations/main.go

@@ -0,0 +1,61 @@
+package main
+
+import (
+	"fmt"
+)
+
+//Runtime: 8 ms, faster than 83.59% of Go online submissions for Permutations.
+//func permute(nums []int) [][]int {
+//	var add func(item []int, addList []int) [][]int
+//	add = func(item []int, addList []int) [][]int {
+//		if len(addList) == 0 {
+//			return [][]int{item}
+//		}
+//		ret := [][]int{}
+//		for i := 0; i < len(addList); i++ {
+//			tmpItem := make([]int, len(item))
+//			tmpAddList := make([]int, len(addList))
+//			copy(tmpItem, item)
+//			copy(tmpAddList, addList)
+//			tmpItem = append(tmpItem, tmpAddList[i])
+//			if i == len(addList)-1 {
+//				tmpAddList = tmpAddList[:i]
+//			} else {
+//				tmpAddList = append(tmpAddList[:i], tmpAddList[i+1:]...)
+//			}
+//			tmp := add(tmpItem, tmpAddList)
+//			ret = append(ret, tmp...)
+//		}
+//		return ret
+//	}
+//	return add([]int{}, nums)
+//}
+
+//只使用原数组切片，没有tmp中间空间
+//Runtime: 4 ms, faster than 100.00% of Go online submissions for Permutations.
+func permute(nums []int) [][]int {
+	var allPermutations [][]int
+	var genPermutation func(nums []int, allPermutations *[][]int, index int)
+	genPermutation = func(nums []int, allPermutations *[][]int, index int) {
+		if index == len(nums) {
+			*allPermutations = append(*allPermutations, append([]int{}, nums...))
+			return
+		}
+		for i := index; i < len(nums); i++ {
+			if i == index {
+				genPermutation(nums, allPermutations, index+1)
+			} else {
+				nums[i], nums[index] = nums[index], nums[i]
+				genPermutation(nums, allPermutations, index+1)
+				nums[i], nums[index] = nums[index], nums[i]
+			}
+		}
+	}
+	genPermutation(nums, &allPermutations, 0)
+	return allPermutations
+}
+
+func main() {
+	var data = []int{4, 5, 2, 1}
+	fmt.Println(permute(data))
+}

code/047. Permutations II/README.md

@@ -0,0 +1,34 @@
+# 47. Permutations II
+
+Given a collection of numbers that might contain duplicates, return all possible unique permutations.
+
+##### Example:
+
+Input: [1,1,2]
+
+Output:
+
+```text
+[
+  [1,1,2],
+  [1,2,1],
+  [2,1,1]
+]
+```
+
+
+给定一个可包含重复数字的序列，返回所有不重复的全排列。
+
+##### 示例:
+
+输入: [1,1,2]
+
+输出:
+
+```text
+[
+  [1,1,2],
+  [1,2,1],
+  [2,1,1]
+]
+```

code/047. Permutations II/main.go

@@ -0,0 +1,71 @@
+package main
+
+import (
+	"fmt"
+)
+
+//在一的基础上过滤相同值的递归
+//Runtime: 12 ms, faster than 100.00% of Go online submissions for Permutations II.
+//func permuteUnique(nums []int) [][]int {
+//	sort.Ints(nums)
+//	var add func(item []int, addList []int) [][]int
+//	add = func(item []int, addList []int) [][]int {
+//		if len(addList) == 0 {
+//			return [][]int{item}
+//		}
+//		ret := [][]int{}
+//		for i := 0; i < len(addList); i++ {
+//			if i != 0 && addList[i] == addList[i-1] {
+//				continue
+//			}
+//			tmpItem := make([]int, len(item))
+//			tmpAddList := make([]int, len(addList))
+//			copy(tmpItem, item)
+//			copy(tmpAddList, addList)
+//			tmpItem = append(tmpItem, tmpAddList[i])
+//			if i == len(addList)-1 {
+//				tmpAddList = tmpAddList[:i]
+//			} else {
+//				tmpAddList = append(tmpAddList[:i], tmpAddList[i+1:]...)
+//			}
+//			tmp := add(tmpItem, tmpAddList)
+//			ret = append(ret, tmp...)
+//		}
+//		return ret
+//	}
+//	return add([]int{}, nums)
+//}
+
+//由于在基础数组进行交换操作，所以无法保证有序，使用map确认是否已经有相同值的递归
+//Runtime: 12 ms, faster than 100.00% of Go online submissions for Permutations II.
+func permuteUnique(nums []int) [][]int {
+	var allPermutations [][]int
+	var genPermutation func(nums []int, allPermutations *[][]int, index int)
+	genPermutation = func(nums []int, allPermutations *[][]int, index int) {
+		if index == len(nums) {
+			*allPermutations = append(*allPermutations, append([]int{}, nums...))
+			return
+		}
+		tmp := map[int]bool{}
+		for i := index; i < len(nums); i++ {
+			if i == index {
+				genPermutation(nums, allPermutations, index+1)
+			} else {
+				if tmp[nums[i]] {
+					continue
+				}
+				nums[i], nums[index] = nums[index], nums[i]
+				genPermutation(nums, allPermutations, index+1)
+				nums[i], nums[index] = nums[index], nums[i]
+			}
+			tmp[nums[i]] = true
+		}
+	}
+	genPermutation(nums, &allPermutations, 0)
+	return allPermutations
+}
+
+func main() {
+	var data = []int{0, 1, 0, 0, 9}
+	fmt.Println(permuteUnique(data))
+}

code/048. Rotate Image/README.md

@@ -0,0 +1,109 @@
+# 48. Rotate Image
+
+You are given an n x n 2D matrix representing an image.
+
+Rotate the image by 90 degrees (clockwise).
+
+##### Note:
+
+You have to rotate the image in-place, which means you have to modify the input 2D matrix directly. DO NOT allocate another 2D matrix and do the rotation.
+
+##### Example 1:
+
+Given input matrix =
+
+```text
+[
+  [1,2,3],
+  [4,5,6],
+  [7,8,9]
+],
+```
+
+rotate the input matrix in-place such that it becomes:
+
+```text
+[
+  [7,4,1],
+  [8,5,2],
+  [9,6,3]
+]
+```
+
+##### Example 2:
+
+Given input matrix =
+
+```text
+[
+  [ 5, 1, 9,11],
+  [ 2, 4, 8,10],
+  [13, 3, 6, 7],
+  [15,14,12,16]
+],
+```
+
+rotate the input matrix in-place such that it becomes:
+
+```text
+[
+  [15,13, 2, 5],
+  [14, 3, 4, 1],
+  [12, 6, 8, 9],
+  [16, 7,10,11]
+]
+```
+
+给定一个 n × n 的二维矩阵表示一个图像。
+
+将图像顺时针旋转 90 度。
+
+##### 说明：
+
+你必须在原地旋转图像，这意味着你需要直接修改输入的二维矩阵。请不要使用另一个矩阵来旋转图像。
+
+##### 示例 1:
+
+给定 matrix =
+
+```text
+[
+  [1,2,3],
+  [4,5,6],
+  [7,8,9]
+],
+```
+
+原地旋转输入矩阵，使其变为:
+
+```text
+[
+  [7,4,1],
+  [8,5,2],
+  [9,6,3]
+]
+```
+
+##### 示例 2:
+
+给定 matrix =
+
+```text
+[
+  [ 5, 1, 9,11],
+  [ 2, 4, 8,10],
+  [13, 3, 6, 7],
+  [15,14,12,16]
+],
+```
+
+原地旋转输入矩阵，使其变为:
+
+```text
+[
+  [15,13, 2, 5],
+  [14, 3, 4, 1],
+  [12, 6, 8, 9],
+  [16, 7,10,11]
+]
+```