Given an array of size n, find the majority element. The majority element is the element that appears more than ⌊ n/2 ⌋
times.
You may assume that the array is non-empty and the majority element always exist in the array.
这道题其实可以用比较取巧的方法做。因为在这里marjority element的定义是整个数列中至少一半的数字都是它,所以当我们sorting了整个数列,中间的那个数肯定是Marjority element。所以非常简单,考虑下length为1的特殊情况就可。代码如下。
public class Solution { public int majorityElement(int[] nums) { if(nums.length==1){ return nums[0]; } Arrays.sort(nums); return nums[nums.length/2]; } }
当然了还有比较常规的,老实按照loop来计算的。这个思路就很简单了。代码如下。
public class Solution { public int majorityElement(int[] num) { if(num.length==1){ return num[0]; } Arrays.sort(num); int test=num[0]; int count=1; for(int i=1; i<num.length; i++){ if(num[i] == test){ count++; if(count > num.length/2) return num[i]; }else{ count=1; test = num[i]; } } return 0; } }