Next Permutation

Author: za-bannai

go/next_permutation.go

@@ -0,0 +1,27 @@
+//lint:file-ignore U1000 Ignore all unused code
+package main
+
+import "sort"
+
+func nextPermutation(nums []int) {
+	for i := len(nums) - 1; i > 0; i-- {
+		if nums[i-1] < nums[i] {
+			minN := nums[i]
+			idx := i
+			for j := i; j < len(nums); j++ {
+				if nums[j] < minN && nums[i-1] < nums[j] {
+					idx = j
+					minN = nums[j]
+				}
+			}
+			nums[i-1], nums[idx] = nums[idx], nums[i-1]
+			sort.Slice(nums[i:], func(a, b int) bool {
+				return nums[i+a] < nums[i+b]
+			})
+			return
+		}
+	}
+	sort.Slice(nums, func(a, b int) bool {
+		return nums[a] < nums[b]
+	})
+}