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.
Credits:
Special thanks to @ts for adding
this problem and creating all test cases.
每找出两个不同的element,则成对删除。最终剩下的一定就是所求的。
(因为比别人多还有另外一种解释,就是你的票抵消了我的一部分票后,我还有剩。)
可扩展到? n/k ?的情况,每k个不同的element进行成对删除。
class Solution { public: int majorityElement(vector<int> &num) { int nTimes = 0; int candidate = 0; for(int i = 0; i < num.size(); i ++) { if(nTimes == 0)//选择新的候选 { candidate = num[i]; nTimes = 1; } else { if(candidate == num[i]) nTimes ++; else nTimes --; } } return candidate; } };
原文:http://blog.csdn.net/sxhlovehmm/article/details/46433199