From e6cf2507e09a89a6f24b102fd5eb68cc58981a16 Mon Sep 17 00:00:00 2001
From: CodingGorit <5571237+CodingGorit@user.noreply.gitee.com>
Date: Fri, 15 Mar 2024 02:21:43 +0000
Subject: [PATCH] Author: CodingGorit<gorit@qq.com>.

Commit Date: 2024/03/15.
Commit Type: leetcode 076.
Commit Description: solve the leetcode 076 of minimum-window-substring.

Signed-off-by: CodingGorit <5571237+CodingGorit@user.noreply.gitee.com>
---
 .../076 minimum-window-substring/index.ts     | 54 +++++++++++++++++++
 1 file changed, 54 insertions(+)

diff --git a/leetcode-coding/leetcode/076 minimum-window-substring/index.ts b/leetcode-coding/leetcode/076 minimum-window-substring/index.ts
index 9655574..d8e5896 100644
--- a/leetcode-coding/leetcode/076 minimum-window-substring/index.ts	
+++ b/leetcode-coding/leetcode/076 minimum-window-substring/index.ts	
@@ -82,3 +82,57 @@ function minWindow(s: string, t: string): string {
 
     return s.slice(begin, begin + minLen + 1); // Include the end character in the result
 }
+
+function minWindow_two(s: string, t: string): string {
+    // 验证输入参数
+    if (s.length === 0 || t.length === 0) {
+        return "";
+    }
+    // 使用哈希表记录t中每个字符的出现次数
+    const targetCounts: Record<string, number> = {};
+    for (let char of t) {
+        targetCounts[char] = (targetCounts[char] || 0) + 1;
+    }
+    // 初始化窗口起始位置和最小子串的起始位置
+    let start = 0,
+        end = 0,
+        minLength = Infinity,
+        validWindowStart = 0,
+        validCount = t.length;
+
+    while (end < s.length) {
+        const currentChar = s[end];
+        if (targetCounts[currentChar] !== undefined) {
+            // 当前字符是目标字符之一，则目标字符计数减一
+            targetCounts[currentChar]--;
+            // 如果当前字符计数 >= 0，说明当前窗口包含了该字符所需的全部实例
+            if (targetCounts[currentChar] >= 0) {
+                validCount--;
+            }
+        }
+        // 当窗口包含了t中所有字符时，尝试缩小窗口
+        while (validCount === 0) {
+            // 更新最小子串长度和起始位置
+            if (end - start + 1 < minLength) {
+                minLength = end - start + 1;
+                validWindowStart = start;
+            }
+            const startChar = s[start];
+            if (targetCounts[startChar] !== undefined) {
+                // 当前窗口包含的实例数过多，需要移除一个
+                targetCounts[startChar]++;
+                // 如果移除后该字符计数 > 0，说明当前窗口多了一个该字符实例
+                if (targetCounts[startChar] > 0) {
+                    validCount++;
+                }
+            }
+            // 缩小窗口
+            start++;
+        }
+        // 扩展窗口
+        end++;
+    }
+
+    // 如果没有找到有效子串，返回空字符串
+    return minLength === Infinity ? "" : s.substr(validWindowStart, minLength);
+}
\ No newline at end of file
-- 
Gitee