16.15. Master Mind

中文文档

Description

The Game of Master Mind is played as follows:

The computer has four slots, and each slot will contain a ball that is red (R). yellow (Y). green (G) or blue (B). For example, the computer might have RGGB (Slot #1 is red, Slots #2 and #3 are green, Slot #4 is blue).

You, the user, are trying to guess the solution. You might, for example, guess YRGB.

When you guess the correct color for the correct slot, you get a "hit:' If you guess a color that exists but is in the wrong slot, you get a "pseudo-hit:' Note that a slot that is a hit can never count as a pseudo-hit.

For example, if the actual solution is RGBY and you guess GGRR, you have one hit and one pseudo-hit. Write a method that, given a guess and a solution, returns the number of hits and pseudo-hits.

Given a sequence of colors solution, and a guess, write a method that return the number of hits and pseudo-hit answer, where answer[0] is the number of hits and answer[1] is the number of pseudo-hit.

Example:

Input:  solution="RGBY",guess="GGRR"

Output:  [1,1]

Explanation:  hit once, pseudo-hit once.

Note:

• len(solution) = len(guess) = 4
• There are only "R","G","B","Y" in solution and guess.

Solutions

Python3

Java

JavaScript

/**
 * @param {string} solution
 * @param {string} guess
 * @return {number[]}
 */
var masterMind = function (solution, guess) {
    let counts1 = { R: 0, G: 0, B: 0, Y: 0 };
    let counts2 = { R: 0, G: 0, B: 0, Y: 0 };
    let res1 = 0;
    for (let i = 0; i < solution.length; i++) {
        let s1 = solution.charAt(i),
            s2 = guess.charAt(i);
        if (s1 == s2) {
            res1++;
        } else {
            counts1[s1] += 1;
            counts2[s2] += 1;
        }
    }
    let res2 = ["R", "G", "B", "Y"].reduce(
        (a, c) => a + Math.min(counts1[c], counts2[c]),
        0
    );
    return [res1, res2];
};

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