QUESTION:

Given two integers, num and t. A number is achievable if it can become equal to num after applying the following operation:

Increase or decrease the number by 1, and simultaneously increase or decrease num by 1. Return the maximum achievable number after applying the operation at most t times.

Example 1:

Input: num = 4, t = 1

Output: 6

Explanation:

Apply the following operation once to make the maximum achievable number equal to num:

Decrease the maximum achievable number by 1, and increase num by 1. Example 2:

Input: num = 3, t = 2

Output: 7

Explanation:

Apply the following operation twice to make the maximum achievable number equal to num:

Decrease the maximum achievable number by 1, and increase num by 1.

Constraints:

1 <= num, t <= 50

EXPLANATION:

比较简单, 假设maxachievable是x, 那么对x减去t次, num加上t次. 就是最后的值. 也就是 x - t = num + t . 得到 x = num + t + t.

SOLUTION:

class Solution {
    func theMaximumAchievableX(_ num: Int, _ t: Int) -> Int {
        return num + (2 * t)
    }
}