这题也没有什么好的解法，在我看来就是每次从左下角转一圈，一直循环，直到结果达到一定的数目。附代码：

class Solution(object):
    def spiralMatrixIII(self, R, C, r0, c0):
        """
        :type R: int
        :type C: int
        :type r0: int
        :type c0: int
        :rtype: List[List[int]]
        """
        start_x = r0
        start_y = c0
        result = [[r0,c0]]
        if c0 + 1 < C:
            result.append([r0,c0+1])
            if r0 + 1 < R:
                result.append([r0+1,c0+1])
        if r0 + 1 < R:
            result.append([r0+1, c0])
        r0 += 1
        c0 -= 1
        step = 2
        while len(result) < R*C :
            if 0<= r0 < R and 0<= c0 < C:
                result.append([r0,c0])
                if len(result) >= R*C:
                    return result
            for i in range(step):
                r0 -= 1
                if 0 <= r0 < R and 0 <= c0 < C:
                    result.append([r0,c0])
                    if len(result) >= R*C:
                        return result
            for i in range(step+1):
                c0 += 1
                if 0 <= r0 < R and 0 <= c0 < C:
                    result.append([r0,c0])
                    if len(result) >= R*C:
                        return result
            for i in range(step+1):
                r0 += 1
                if 0 <= r0 < R and 0 <= c0 < C:
                    result.append([r0,c0])
                    if len(result) >= R*C:
                        return result
            for i in range(step+1):
                c0 -= 1
                if 0 <= r0 < R and 0 <= c0 < C:
                    result.append([r0,c0])
                    if len(result) >= R*C:
                        return result
            step += 2
            c0 -= 1
        return result