codility

Author: kimi0230

Codility/Lesson/0007.Stacks-and-Queues/Brackets/README.md

@@ -28,4 +28,56 @@ Copyright 2009–2021 by Codility Limited. All Rights Reserved. Unauthorized cop
 ## 解題思路
 將左括號都放入stack. 遇到右括號時將stack pop出來並檢查pop出來的左括號是否跟右括號配對.
 ## 來源
-https://app.codility.com/programmers/lessons/7-stacks_and_queues/brackets/
+https://app.codility.com/programmers/lessons/7-stacks_and_queues/brackets/
+
+## 解答
+https://github.com/kimi0230/LeetcodeGolang/blob/master/Codility/Lesson/0007.Stacks-and-Queues/Brackets/Brackets.go
+
+
+```go
+package Brackets
+
+import (
+	"LeetcodeGolang/Utility/structures"
+)
+
+func Solution(S string) int {
+	if len(S) == 0 {
+		return 1
+	}
+	if len(S)%2 != 0 {
+		return 0
+	}
+
+	BracketMap := map[string]string{
+		")": "(",
+		"]": "[",
+		"}": "{",
+	}
+
+	stack := structures.NewArrayStack()
+	for _, v := range S {
+		val := string(v)
+		if val == "(" || val == "[" || val == "{" {
+			stack.Push(val)
+		} else if val == ")" || val == "]" || val == "}" {
+			if stack.IsEmpty() {
+				return 0
+			}
+
+			topVal := stack.Top()
+			if topVal == BracketMap[val] {
+				stack.Pop()
+			} else {
+				// 找不到可配對的括號
+				return 0
+			}
+		}
+	}
+	if stack.IsEmpty() {
+		return 1
+	} else {
+		return 0
+	}
+}
+```

Codility/Lesson/0007.Stacks-and-Queues/Fish/README.md

@@ -51,4 +51,39 @@ A: 活魚的大小, B: 魚游的方向. 如果於相遇的話大魚會吃掉小
 如果值為0且stack為空, 代表沒遇到下游的魚所以活魚++
 
 ## 來源
-https://app.codility.com/programmers/lessons/7-stacks_and_queues/fish/
+https://app.codility.com/programmers/lessons/7-stacks_and_queues/fish/
+
+## 解答
+https://github.com/kimi0230/LeetcodeGolang/blob/master/Codility/Lesson/0007.Stacks-and-Queues/Fish/Fish.go
+
+
+```go
+package Fish
+
+import "LeetcodeGolang/Utility/structures"
+
+func Solution(A []int, B []int) int {
+	stack := structures.NewArrayStack()
+	aliveFish := 0
+	for idx, val := range B {
+		if val == 1 {
+			stack.Push(A[idx])
+		} else {
+			// 繼續往下游
+			for !stack.IsEmpty() {
+				if stack.Top().(int) < A[idx] {
+					// stack的魚比遇到的魚還小, stack被吃掉
+					stack.Pop()
+				} else {
+					break
+				}
+			}
+			if stack.IsEmpty() {
+				aliveFish++
+			}
+		}
+	}
+	return aliveFish + stack.Size()
+}
+
+```

Codility/Lesson/0007.Stacks-and-Queues/Nesting/README.md

@@ -29,4 +29,38 @@ Copyright 2009–2021 by Codility Limited. All Rights Reserved. Unauthorized cop
 與Bracket類似
 
 ## 來源
-https://app.codility.com/programmers/lessons/7-stacks_and_queues/nesting/
+https://app.codility.com/programmers/lessons/7-stacks_and_queues/nesting/
+
+## 解答
+https://github.com/kimi0230/LeetcodeGolang/blob/master/Codility/Lesson/0007.Stacks-and-Queues/Nesting/Nesting.go
+
+
+```go
+package Nesting
+
+import "LeetcodeGolang/Utility/structures"
+
+func Solution(S string) int {
+	if len(S) == 0 {
+		return 1
+	}
+	if len(S)%2 != 0 {
+		return 0
+	}
+
+	stack := structures.NewArrayStack()
+	for _, v := range S {
+		val := string(v)
+		if val == "(" {
+			stack.Push(val)
+		} else if val == ")" {
+			stack.Pop()
+		}
+	}
+	if stack.IsEmpty() {
+		return 1
+	} else {
+		return 0
+	}
+}
+```

Codility/Lesson/0007.Stacks-and-Queues/StoneWall/README.md

@@ -41,4 +41,29 @@ H[N-1]大表牆N-1米處到最右的高度
 
 ## 來源
 * https://app.codility.com/programmers/lessons/7-stacks_and_queues/stone_wall/
-* https://github.com/Anfany/Codility-Lessons-By-Python3/blob/master/L7_Stacks%20and%20Queues/7.4%20StoneWall.md
+* https://github.com/Anfany/Codility-Lessons-By-Python3/blob/master/L7_Stacks%20and%20Queues/7.4%20StoneWall.md
+
+## 解答
+https://github.com/kimi0230/LeetcodeGolang/blob/master/Codility/Lesson/0007.Stacks-and-Queues/StoneWall/StoneWall.go
+
+
+```go
+package StoneWall
+
+import "LeetcodeGolang/Utility/structures"
+
+func Solution(H []int) int {
+	stack := structures.NewArrayStack()
+	result := 0
+	for _, v := range H {
+		for !stack.IsEmpty() && stack.Top().(int) > v {
+			stack.Pop()
+		}
+		if stack.IsEmpty() || stack.Top().(int) < v {
+			stack.Push(v)
+			result++
+		}
+	}
+	return result
+}
+```

Codility/Lesson/0008.Leader/Dominator/README.md

@@ -38,4 +38,50 @@ Copyright 2009–2021 by Codility Limited. All Rights Reserved. Unauthorized cop
 是的話返回此數任一個index, 反之返回-1
 
 ## 來源
-https://app.codility.com/programmers/lessons/8-leader/dominator/
+https://app.codility.com/programmers/lessons/8-leader/dominator/
+
+## 解答
+https://github.com/kimi0230/LeetcodeGolang/blob/master/Codility/Lesson/0008.Leader/Dominator/Dominator.go
+
+
+```go
+package Dominator
+
+import (
+	"math"
+)
+
+func Solution(A []int) int {
+	mapInt := make(map[int]int, len(A))
+
+	for _, v := range A {
+		if _, ok := mapInt[v]; !ok {
+			mapInt[v] = 1
+		} else {
+			mapInt[v]++
+		}
+	}
+
+	maxCount := 0
+	maxVal := 0
+	for k, v := range mapInt {
+		if v > maxCount {
+			maxCount = v
+			maxVal = k
+		}
+	}
+	minIndex := -1
+	for k, v := range A {
+		if v == maxVal {
+			minIndex = k
+			break
+		}
+	}
+
+	if maxCount > int(math.Floor(float64(len(A))/2.0)) {
+		return minIndex
+	} else {
+		return -1
+	}
+}
+```

Codility/Lesson/0008.Leader/EquiLeader/README.md

@@ -56,4 +56,47 @@ Copyright 2009–2021 by Codility Limited. All Rights Reserved. Unauthorized cop
 
 ## 來源
 * https://app.codility.com/programmers/lessons/8-leader/equi_leader/
-* https://github.com/Anfany/Codility-Lessons-By-Python3/blob/master/L8_Leader/8.1%20EquiLeader.md
+* https://github.com/Anfany/Codility-Lessons-By-Python3/blob/master/L8_Leader/8.1%20EquiLeader.md
+
+## 解答
+https://github.com/kimi0230/LeetcodeGolang/blob/master/Codility/Lesson/0008.Leader/EquiLeader/EquiLeader.go
+
+
+```go
+package EquiLeader
+
+func Solution(A []int) int {
+	leaderDict := make(map[int]int)
+	for i := 0; i < len(A); i++ {
+		if _, ok := leaderDict[A[i]]; ok {
+			leaderDict[A[i]]++
+		} else {
+			leaderDict[A[i]] = 1
+		}
+	}
+
+	leader := 0
+	times := 0
+	for k, v := range leaderDict {
+		if v > times {
+			times = v
+			leader = k
+		}
+	}
+
+	equiCount := 0
+	count := 0 // 超頻數已出現的次數
+
+	for index, v := range A {
+		if v == leader {
+			count++
+		}
+		if count > (index+1)/2 && (times-count) > (len(A)-(index+1))/2 {
+			equiCount++
+		}
+
+	}
+
+	return equiCount
+}
+```

Codility/Lesson/0009.Maximum-Slice-Problem/MaxDoubleSliceSum/README.md

@@ -61,4 +61,45 @@ A[X+1]到A[Y-1] + A[Y+1]到A[Z-1] 最大的和
 
 ## 來源
 * https://app.codility.com/programmers/lessons/9-maximum_slice_problem/max_double_slice_sum/
-* https://github.com/Anfany/Codility-Lessons-By-Python3/blob/master/L9_Maximum%20Slice%20Problem/9.3%20%20MaxDoubleSliceSum.md
+* https://github.com/Anfany/Codility-Lessons-By-Python3/blob/master/L9_Maximum%20Slice%20Problem/9.3%20%20MaxDoubleSliceSum.md
+
+## 解答
+https://github.com/kimi0230/LeetcodeGolang/blob/master/Codility/Lesson/0009.Maximum-Slice-Problem/MaxDoubleSliceSum/MaxDoubleSliceSum.go
+
+
+```go
+package MaxDoubleSliceSum
+
+import (
+	"math"
+)
+
+func Solution(A []int) int {
+	if len(A) < 4 {
+		return 0
+	}
+	N := len(A) - 2
+	forwardSum := make([]int, N)
+	reverseSum := make([]int, N)
+
+	//  0 ≤ X < Y < Z < N,
+	//  A[X + 1] + A[X + 2] + ... + A[Y − 1] + A[Y + 1] + A[Y + 2] + ... + A[Z − 1].
+	// 			A : [ 3,  2, 6, -1,  4,  5, -1, 2]
+	// forwardSum : [ 0,  2, 8,  7, 11, 16]
+	// reverseSum : [14,  8, 9,  5,  0,  0]
+	for i := 0; i < N-1; i++ {
+		forwardVal := A[i+1]
+		reverseVal := A[N-i]
+
+		forwardSum[i+1] = int(math.Max(0, float64(forwardVal)+float64(forwardSum[i])))
+		reverseSum[N-i-2] = int(math.Max(0, float64(reverseVal)+float64(reverseSum[N-i-1])))
+	}
+
+	combineMax := math.MinInt64
+	for i := 0; i < N; i++ {
+		combineMax = int(math.Max(float64(combineMax), float64(forwardSum[i])+float64(reverseSum[i])))
+	}
+
+	return combineMax
+}
+```

Codility/Lesson/0009.Maximum-Slice-Problem/MaxProfit/README.md

@@ -43,4 +43,29 @@ Copyright 2009–2021 by Codility Limited. All Rights Reserved. Unauthorized cop
 尋遍整個array, 找出最小的買入金額, 同時計算當前的賣出金額-最小買入金額, 得出最大利潤
 
 ## 來源
-https://app.codility.com/programmers/lessons/9-maximum_slice_problem/max_profit/
+https://app.codility.com/programmers/lessons/9-maximum_slice_problem/max_profit/
+
+## 解答
+https://github.com/kimi0230/LeetcodeGolang/blob/master/Codility/Lesson/0009.Maximum-Slice-Problem/MaxProfit/MaxProfit.go
+
+
+```go
+package MaxProfit
+
+import (
+	"math"
+)
+
+func Solution(A []int) int {
+	minBuyPrice := math.MaxFloat64
+	maxProfit := 0.0
+
+	for _, v := range A {
+		minBuyPrice = math.Min(minBuyPrice, float64(v))
+		maxProfit = math.Max(maxProfit, float64(v)-minBuyPrice)
+	}
+
+	return int(maxProfit)
+}
+
+```

Codility/Lesson/0009.Maximum-Slice-Problem/MaxSliceSum/README.md

@@ -34,4 +34,29 @@ Copyright 2009–2021 by Codility Limited. All Rights Reserved. Unauthorized cop
 當下的值跟當下的值加上先前的和, 取最大值. 再將剛剛算出的最大值跟紀錄中的最大值比較,取最大值
 
 ## 來源
-https://app.codility.com/programmers/lessons/9-maximum_slice_problem/max_slice_sum/
+https://app.codility.com/programmers/lessons/9-maximum_slice_problem/max_slice_sum/
+
+## 解答
+https://github.com/kimi0230/LeetcodeGolang/blob/master/Codility/Lesson/0009.Maximum-Slice-Problem/MaxSliceSum/MaxSliceSum.go
+
+
+```go
+package MaxSliceSum
+
+import (
+	"math"
+)
+
+func Solution(A []int) int {
+	if len(A) == 1 {
+		return A[0]
+	}
+	result := math.MinInt64
+	sum := math.MinInt64
+	for i := 0; i < len(A); i++ {
+		sum = int(math.Max(float64(A[i]), float64(A[i])+float64(sum)))
+		result = int(math.Max(float64(sum), float64(result)))
+	}
+	return result
+}
+```