[Swift]LeetCode390. 消除游戏 | Elimination Game
There is a list of sorted integers from 1 to?n. Starting from left to right,remove the first number and every other number afterward until you reach the end of the list. Repeat the previous step again,but this time from right to left,remove the right most number and every other number from the remaining numbers. We keep repeating the steps again,alternating left to right and right to left,until a single number remains. Find the last number that remains starting with a list of length?n. Example: Input: n = 9,1 2 3 4 5 6 7 8 9 2 4 6 8 2 6 6 Output: 6 给定一个从1 到 n 排序的整数列表。 示例: 输入: n = 9,1 2 3 4 5 6 7 8 9 2 4 6 8 2 6 6 输出: 6 20ms 1 class Solution { 2 func lastRemaining(_ n: Int) -> Int { 3 return n == 1 ? 1 : 2 * (n / 2 + 1 - lastRemaining(n / 2)) 4 } 5 } 28ms 1 class Solution { 2 func clear(lun: Int,lunCount: Int,lastNum: Int,n: Int) -> Int { 3 let lastSpan = (1<<(lun - 1)) 4 var tmpLastNum = lastNum 5 6 if lun % 2 == 0 || (n / lastSpan) % 2 != 0 { 7 tmpLastNum = tmpLastNum - lastSpan 8 } 9 10 if lun == lunCount { return tmpLastNum } 11 return clear(lun: lun + 1,12 lunCount: lunCount,13 lastNum: tmpLastNum,14 n: n) 15 } 16 17 func lastRemaining(_ n: Int) -> Int { 18 if n == 1 { return 1 } 19 var lunCount = 0 20 var total = n 21 while total != 1 { 22 total = total / 2 23 lunCount += 1 24 } 25 return clear(lun: 1,26 lunCount: lunCount,27 lastNum: n,28 n: n) 29 } 30 } (编辑:李大同) 【声明】本站内容均来自网络,其相关言论仅代表作者个人观点,不代表本站立场。若无意侵犯到您的权利,请及时与联系站长删除相关内容! |