标签：public const using only NPU imp for algo ber
Given an array containing n distinct numbers taken from 0, 1, 2, ..., n, find the one that is missing from the array.
Example 1:
Input: [3,0,1] Output: 2
Example 2:
Input: [9,6,4,2,3,5,7,0,1] Output: 8
Note:
Your algorithm should run in linear runtime complexity. Could you implement it using only constant extra space complexity?
因为是由0~n组成的数组，只缺少一个数字，可以先通过公式计算出应有的和，再遍历数组一个个减去，剩下的数就是missing number
时间：O(N)，空间：O(1)
class Solution { public int missingNumber(int[] nums) { int n = nums.length; int sum = n * (n + 1) / 2; for(int i = 0; i < n; i++) { sum -= nums[i]; } return sum; } }
标签：public const using only NPU imp for algo ber
原文地址：https://www.cnblogs.com/fatttcat/p/10039518.html
