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top-100-liked/11_test.go

@@ -0,0 +1,42 @@
+package top100liked
+
+import (
+	"fmt"
+	"testing"
+)
+
+// https://leetcode.cn/problems/sliding-window-maximum/?envType=study-plan-v2&envId=top-100-liked
+
+func maxSlidingWindow(nums []int, k int) []int {
+	if len(nums) == 0 || k == 0 {
+		return []int{}
+	}
+
+	deque := make([]int, 0) // 存下标，单调递减（对应值）
+	result := make([]int, 0, len(nums)-k+1)
+
+	for i := 0; i < len(nums); i++ {
+		// 1. 从队尾移除所有 <= nums[i] 的下标
+		for len(deque) > 0 && nums[deque[len(deque)-1]] <= nums[i] {
+			deque = deque[:len(deque)-1]
+		}
+		// 2. 加入当前下标
+		deque = append(deque, i)
+		// 3. 如果队首下标已出窗口，移除
+		if deque[0] < i-k+1 {
+			deque = deque[1:]
+		}
+		// 4. 窗口形成后，记录最大值
+		if i >= k-1 {
+			result = append(result, nums[deque[0]])
+		}
+	}
+	return result
+}
+
+func TestS11(t *testing.T) {
+	fmt.Printf("%+v", maxSlidingWindow([]int{1, 3, -1, -3, 5, 3, 6, 7}, 3))
+	fmt.Printf("%+v", maxSlidingWindow([]int{1}, 1))
+	fmt.Printf("%+v", maxSlidingWindow([]int{9, 9, 8, 8, 7, 7, 6, 6}, 2))
+	fmt.Printf("%+v", maxSlidingWindow([]int{10, 9, 8, 7, 6, 5}, 3))
+}