GeeksforGeeks

Author: kimi0230

GeeksforGeeks/SortingAlgorithms/0031.Find-Minimum-Difference-Between-Any-Two-Elements/README.md

@@ -17,4 +17,82 @@ Output : 5
 Minimum difference is between 1 and -4
 
 ## 來源
-* https://www.geeksforgeeks.org/find-minimum-difference-pair/
+* https://www.geeksforgeeks.org/find-minimum-difference-pair/
+
+## 解答
+https://github.com/kimi0230/LeetcodeGolang/blob/master/GeeksforGeeks/SortingAlgorithms/0031.Find-Minimum-Difference-Between-Any-Two-Elements/Find-Minimum-Difference-Between-Any-Two-Elements.go
+
+```go
+package findminimumdifferencebetweenanytwoelements
+
+import (
+	"math"
+	"sort"
+)
+
+/*
+https://yourbasic.org/golang/absolute-value-int-float/
+http://cavaliercoder.com/blog/optimized-abs-for-int64-in-go.html
+fmt.Println(abs(math.MinInt64)) // Output: -9223372036854775808
+
+// 似乎比較快
+func WithTwosComplement(n int64) int64 {
+	y := n >> 63          // y ← x ⟫ 63
+	return (n ^ y) - y    // (x ⨁ y) - y
+}
+*/
+func abs(n int) int {
+	if n < 0 {
+		return -n
+	}
+	return n
+}
+
+func WithTwosComplement(n int64) int64 {
+	y := n >> 63       // y ← x ⟫ 63
+	return (n ^ y) - y // (x ⨁ y) - y
+}
+
+// O(n Log n)
+func FindMinDiff(nums []int) int {
+	if len(nums) <= 0 {
+		return 0
+	}
+	sort.Ints(nums) // O(n Log n)
+
+	minSize := math.MaxInt32
+
+	// O(n)
+	for i := 1; i < len(nums); i++ {
+		tmp := int(math.Abs(float64(nums[i] - nums[i-1])))
+		if minSize > tmp {
+			minSize = tmp
+		}
+	}
+
+	if minSize == math.MaxInt32 {
+		minSize = 0
+	}
+	return minSize
+}
+
+func FindMinDiff2(nums []int) int {
+	if len(nums) <= 0 {
+		return 0
+	}
+	sort.Ints(nums)
+
+	minSize := math.MaxInt32
+	for i := 1; i < len(nums); i++ {
+		tmp := abs(nums[i] - nums[i-1])
+		if minSize > tmp {
+			minSize = tmp
+		}
+	}
+
+	if minSize == math.MaxInt32 {
+		minSize = 0
+	}
+	return minSize
+}
+```