小黑代码1:滑动窗口

class Solution:
    def findAnagrams(self, s: str, p: str) -> List[int]:
        # 字符串长度
        n_s = len(s)
        n_p = len(p)
        if n_s < n_p:
            return []
        # 差值数组
        arr = [0] * 26
        # 初始窗口
        for i in range(n_p):
            arr[ord(p[i])-97] -= 1
            arr[ord(s[i])-97] += 1
        # 计算初始窗口差值
        diff = sum([abs(t) for t in arr])
        # 结果数组
        results = []
        if not diff:
            results.append(0)
        # 滑动窗口操作
        for i in range(n_s-n_p):
            if arr[ord(s[i])-97] <= 0:
                diff += 1
            else:
                diff -= 1
            arr[ord(s[i])-97] -= 1
            if arr[ord(s[i+n_p])-97] < 0:
                diff -= 1
            else:
                diff += 1
            arr[ord(s[i+n_p])-97] += 1
            if not diff:
                results.append(i+1)
        return results`class Solution:
    def findAnagrams(self, s: str, p: str) -> List[int]:
        # 字符串长度
        n_s = len(s)
        n_p = len(p)
        if n_s < n_p:
            return []
        # 差值数组
        arr = [0] * 26
        for i in range(n_p):
            arr[ord(p[i])-97] -= 1
        # 定义双指针
        head = 0
        tail = 0
        # 结果数组
        results = []
        # 进行双指针操作
        while tail < n_s:
            # 头指针右移动
            while arr[ord(s[tail])-97] >= 0:
                arr[ord(s[head])-97] -= 1
                head += 1
            arr[ord(s[tail])-97] += 1
            tail += 1
            if tail - head == n_p:
                results.append(head)
        return results`

小黑代码2:双指针法

class Solution:
    def findAnagrams(self, s: str, p: str) -> List[int]:
        # 字符串长度
        n_s = len(s)
        n_p = len(p)
        if n_s < n_p:
            return []
        # 差值数组
        arr = [0] * 26
        for i in range(n_p):
            arr[ord(p[i])-97] -= 1
        # 定义双指针
        head = 0
        tail = 0
        # 结果数组
        results = []
        # 进行双指针操作
        while tail < n_s:
            # 头指针右移动
            while arr[ord(s[tail])-97] >= 0:
                arr[ord(s[head])-97] -= 1
                head += 1
            arr[ord(s[tail])-97] += 1
            tail += 1
            if tail - head == n_p:
                results.append(head)
        return results

小黑生活

吃黄姐火锅

重庆小巷子里闲逛，前往中山四路

到达中山四路

坐轻轨去李子坝，吃苕皮，看穿楼轻轨

前往重庆江北机场

发现海底捞学生优惠用不了了

复查眼睛，喝喜茶

来一碗门框卤煮

抢去西藏的票

搓澡汗蒸，身上全是泥

疯狂星期四，见三年的研究生线上同门，一起喝了北冰洋，好久不摸零钱了