• 双指针
• https://leetcode-cn.com/problems/max-consecutive-ones-iii/
  

    def GetMaxConsecutiveOnes(self, arr, k):
        # write code here
        zero = 0
        left = 0
        res = 0
        for right in range(len(arr)):
            if arr[right] == 0:
                zero += 1
            while zero > k:
                if arr[left] == 0:
                    zero -= 1
                left += 1
            res = max(res, right - left + 1)
        return res

• 螺旋数组
• https://leetcode-cn.com/problems/spiral-matrix/
  

    def SpiralMatrix(self, matrix):
        # write code here
        direction = [[0, 1], [1, 0], [0, -1], [-1, 0]]
        res = []
        x, y = 0, 0
        direct = 0
        for _ in range(len(matrix) * len(matrix[0]) - 1):
            res.append(matrix[x][y])
            matrix[x][y] = 'a'
            while not (0 <= x + direction[direct][0] < len(matrix) and
                       len(matrix[0]) > y + direction[direct][1] >= 0 and
                       matrix[x + direction[direct][0]][y + direction[direct][1]] != 'a'):
                direct = (direct + 1) % 4
            x += direction[direct][0]
            y += direction[direct][1]
        res.append(matrix[x][y])
        return res

• 刚开始想复杂了...
• https://www.nowcoder.com/questionTerminal/97bc02e432bb4744a9e666b6c93d4479
  

    def GetFragment(self, str):
        slide = 1
        for i in range(1, len(str)):
            if str[i] != str[i - 1]:
                slide += 1

        return len(str) // slide