Fix solution 628

Author: halfrost

leetcode/0628.Maximum-Product-of-Three-Numbers/628. Maximum Product of Three Numbers.go

@@ -1,6 +1,7 @@
 package leetcode
 
 import (
+	"math"
 	"sort"
 )
 
@@ -32,28 +33,27 @@ func max(a int, b int) int {
 
 // 解法二 模拟，时间复杂度 O(n)
 func maximumProduct1(nums []int) int {
-	n1, n2, n3 := -1<<63, -1<<63, -1<<63
-	n4, n5 := 0, 0
-	for _, v := range nums {
-		if v > n1 {
-			n3 = n2
-			n2 = n1
-			n1 = v
-		} else if v > n2 {
-			n3 = n2
-			n2 = v
-		} else if v > n3 {
-			n3 = v
+	max := make([]int, 0)
+	max = append(max, math.MinInt64, math.MinInt64, math.MinInt64)
+	min := make([]int, 0)
+	min = append(min, math.MaxInt64, math.MaxInt64)
+	for _, num := range nums {
+		if num > max[0] {
+			max[0], max[1], max[2] = num, max[0], max[1]
+		} else if num > max[1] {
+			max[1], max[2] = num, max[1]
+		} else if num > max[2] {
+			max[2] = num
 		}
-		if v < n4 {
-			n5 = n4
-			n4 = v
-		} else if v < n5 {
-			n5 = v
+		if num < min[0] {
+			min[0], min[1] = num, min[0]
+		} else if num < min[1] {
+			min[1] = num
 		}
 	}
-	if n2*n3 > n4*n5 {
-		return n1 * n2 * n3
+	maxProduct1, maxProduct2 := min[0]*min[1]*max[0], max[0]*max[1]*max[2]
+	if maxProduct1 > maxProduct2 {
+		return maxProduct1
 	}
-	return n1 * n4 * n5
+	return maxProduct2
 }

website/content/ChapterFour/0628.Maximum-Product-of-Three-Numbers.md

@@ -43,6 +43,7 @@ Given an integer array, find three numbers whose product is maximum and output t
 package leetcode
 
 import (
+	"math"
 	"sort"
 )
 
@@ -65,32 +66,38 @@ func maximumProduct(nums []int) int {
 	return max(nums[0]*nums[1]*nums[len(nums)-1], nums[len(nums)-1]*nums[len(nums)-2]*nums[len(nums)-3])
 }
 
+func max(a int, b int) int {
+	if a > b {
+		return a
+	}
+	return b
+}
+
 // 解法二 模拟，时间复杂度 O(n)
 func maximumProduct1(nums []int) int {
-	n1, n2, n3 := -1<<63, -1<<63, -1<<63
-	n4, n5 := 0, 0
-	for _, v := range nums {
-		if v > n1 {
-			n3 = n2
-			n2 = n1
-			n1 = v
-		} else if v > n2 {
-			n3 = n2
-			n2 = v
-		} else if v > n3 {
-			n3 = v
+	max := make([]int, 0)
+	max = append(max, math.MinInt64, math.MinInt64, math.MinInt64)
+	min := make([]int, 0)
+	min = append(min, math.MaxInt64, math.MaxInt64)
+	for _, num := range nums {
+		if num > max[0] {
+			max[0], max[1], max[2] = num, max[0], max[1]
+		} else if num > max[1] {
+			max[1], max[2] = num, max[1]
+		} else if num > max[2] {
+			max[2] = num
 		}
-		if v < n4 {
-			n5 = n4
-			n4 = v
-		} else if v < n5 {
-			n5 = v
+		if num < min[0] {
+			min[0], min[1] = num, min[0]
+		} else if num < min[1] {
+			min[1] = num
 		}
 	}
-	if n2*n3 > n4*n5 {
-		return n1 * n2 * n3
+	maxProduct1, maxProduct2 := min[0]*min[1]*max[0], max[0]*max[1]*max[2]
+	if maxProduct1 > maxProduct2 {
+		return maxProduct1
 	}
-	return n1 * n4 * n5
+	return maxProduct2
 }
 
 ```