[leetcode] 800. Similar RGB Color @ python

原题

In the following, every capital letter represents some hexadecimal digit from 0 to f.

The red-green-blue color “#AABBCC” can be written as “#ABC” in shorthand. For example, “#15c” is shorthand for the color “#1155cc”.

Now, say the similarity between two colors “#ABCDEF” and “#UVWXYZ” is -(AB - UV)^2 - (CD - WX)^2 - (EF - YZ)^2.

Given the color “#ABCDEF”, return a 7 character color that is most similar to #ABCDEF, and has a shorthand (that is, it can be represented as some “#XYZ”

Example 1:
Input: color = “#09f166”
Output: “#11ee66”
Explanation:
The similarity is -(0x09 - 0x11)^2 -(0xf1 - 0xee)^2 - (0x66 - 0x66)^2 = -64 -9 -0 = -73.
This is the highest among any shorthand color.
Note:

color is a string of length 7.
color is a valid RGB color: for i > 0, color[i] is a hexadecimal digit from 0 to f
Any answer which has the same (highest) similarity as the best answer will be accepted.
All inputs and outputs should use lowercase letters, and the output is 7 characters.

解法

使用min(key)的方法, 自定义lambda函数, 选出离s距离最近的字符串.
官方文档: https://docs.python.org/2/library/functions.html#min

代码

class Solution(object):
    def similarRGB(self, color):
        """
        :type color: str
        :rtype: str
        """
        def getClosest(s):
            m = ['00','11','22','33','44','55','66','77','88','99','aa','bb','cc','dd','ee','ff']
            return min(m, key = lambda x: abs(int(x, 16)- int(s,16)))
        
        res = ''
        color = color[1:]
        for i in range(3):
            s = color[2*i:2*i+2]
            res += getClosest(s)
        return '#' +res