# LeetCode 800 Similar RGB Color

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.

One-on-One Algorithm and Coding Training

One-on-One System Design Training

One-on-One Mock Interview

##### Top-notch Professionals

Most recent interview questions and system design topics gathered from aonecode alumnus.
One-to-one online classes. Get feedbacks from real interviewers.