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top-100-liked/70/leetcode_test.go

@@ -0,0 +1,43 @@
+package top100liked
+
+import (
+	"fmt"
+	"strings"
+	"testing"
+	"unicode"
+)
+
+// https://leetcode.cn/problems/decode-string/description/?envType=study-plan-v2&envId=top-100-liked
+
+func decodeString(s string) string {
+	curStr := ""
+	curNum := 0
+	strStack := []string{}
+	numStack := []int{}
+	for _, r := range s {
+		if unicode.IsDigit(r) {
+			curNum = curNum*10 + int(r-'0')
+		} else if unicode.IsLetter(r) {
+			curStr += string(r)
+		} else if r == '[' {
+			strStack = append(strStack, curStr)
+			curStr = ""
+			numStack = append(numStack, curNum)
+			curNum = 0
+		} else if r == ']' {
+			num := numStack[len(numStack)-1]
+			prevStr := strStack[len(strStack)-1]
+			numStack = numStack[:len(numStack)-1]
+			strStack = strStack[:len(strStack)-1]
+			curStr = prevStr + strings.Repeat(curStr, num)
+		}
+	}
+	return curStr
+}
+
+func Test(t *testing.T) {
+	fmt.Println(decodeString("3[a]2[bc]"))
+	fmt.Println(decodeString("3[a2[c]]"))
+	fmt.Println(decodeString("2[abc]3[cd]ef"))
+	fmt.Println(decodeString("abc3[cd]xyz"))
+}

top-100-liked/71/leetcode_test.go

@@ -0,0 +1,62 @@
+package top100liked
+
+import (
+	"fmt"
+	"testing"
+)
+
+// https://leetcode.cn/problems/daily-temperatures/?envType=study-plan-v2&envId=top-100-liked
+
+func dailyTemperatures(temperatures []int) []int {
+	res := make([]int, len(temperatures))
+	stack := make([]int, 0, len(temperatures))
+
+	for i := len(temperatures) - 1; i >= 0; i-- {
+		for len(stack) > 0 && temperatures[stack[len(stack)-1]] <= temperatures[i] {
+			stack = stack[:len(stack)-1]
+		}
+		if len(stack) > 0 {
+			res[i] = stack[len(stack)-1] - i
+		}
+		stack = append(stack, i)
+	}
+
+	return res
+}
+
+// func dailyTemperatures(temperatures []int) []int {
+// 	type item struct {
+// 		Idx  int
+// 		Temp int
+// 	}
+// 	stack := []item{}
+// 	res := make([]int, len(temperatures))
+// 	for i := len(temperatures) - 1; i >= 0; i-- {
+// 		cur := temperatures[i]
+// 		if len(stack) == 0 {
+// 			stack = append(stack, item{i, cur})
+// 			res[i] = 0
+// 		} else {
+// 			for {
+// 				if len(stack) == 0 {
+// 					stack = append(stack, item{i, cur})
+// 					res[i] = 0
+// 					break
+// 				}
+// 				top := stack[len(stack)-1]
+// 				if cur < top.Temp {
+// 					res[i] = top.Idx - i
+// 					stack = append(stack, item{i, cur})
+// 					break
+// 				} else {
+// 					stack = stack[:len(stack)-1] // pop
+// 				}
+// 			}
+// 		}
+// 	}
+// 	return res
+// }
+
+func Test(t *testing.T) {
+	fmt.Printf("%+v", dailyTemperatures([]int{73, 74, 75, 71, 69, 72, 76, 73}))
+}

top-100-liked/72/leetcode_test.go

@@ -0,0 +1,60 @@
+package top100liked
+
+import (
+	"fmt"
+	"testing"
+)
+
+// https://leetcode.cn/problems/largest-rectangle-in-histogram/?envType=study-plan-v2&envId=top-100-liked
+
+// 暴力法，超时
+// func largestRectangleArea(heights []int) int {
+// 	maxArea := 0
+// 	// i 是每个组合中的元素数量
+// 	for i := 1; i <= len(heights); i++ {
+// 		// j 是在整个 heights 中滑动的次数
+// 		for j := 0; j < len(heights)-i+1; j++ {
+// 			// 计算
+// 			maxArea = max(maxArea, slices.Min(heights[j:j+i])*i)
+// 		}
+// 	}
+// 	return maxArea
+// }
+
+func largestRectangleArea(heights []int) int {
+	stack := []int{}
+	maxArea := 0
+	for i := range len(heights) + 1 {
+		if len(stack) == 0 {
+			stack = append(stack, i)
+			continue
+		}
+		var cur int
+		if i == len(heights) {
+			cur = 0
+		} else {
+			cur = heights[i]
+		}
+		if cur >= heights[stack[len(stack)-1]] {
+			stack = append(stack, i)
+		} else {
+			for len(stack) > 0 && heights[stack[len(stack)-1]] > cur {
+				top := stack[len(stack)-1]
+				stack = stack[:len(stack)-1]
+				width := i
+				if len(stack) > 0 {
+					width = i - stack[len(stack)-1] - 1
+				}
+				maxArea = max(maxArea, heights[top]*width)
+			}
+			stack = append(stack, i)
+		}
+	}
+	return maxArea
+}
+
+func Test(t *testing.T) {
+	fmt.Println(largestRectangleArea([]int{2, 1, 5, 6, 2, 3}))
+	fmt.Println(largestRectangleArea([]int{1}))
+	fmt.Println(largestRectangleArea([]int{2, 1, 2}))
+}