problem:
Follow up for "Remove Duplicates":
What if duplicates are allowed at most twice?
For example,
Given sorted array A = [1,1,1,2,2,3]
,
Your function should return length = 5
,
and A is now [1,1,2,2,3]
.
thinking:
(1)先对数组排序
(2)从左往右遍历数组,出现相同元素开始计数,当重复出现次数超过2次时,用后面的元素覆盖多出的元素(数组往前移动)。
code:
class Solution { public: int removeDuplicates(int A[], int n) { if(n<3) return n; int i=0; int j=0; sort(A,A+n); while(j<n) { while(j<n&&A[j]==A[++j]); //J定位到最后一个相同元素的下一个位置 if(j-i>2) { int num=j-i-2; //多余的元素的个数 for(int k=0;k<n-j;k++) //往左移动覆盖多余的元素 A[i+2+k]=A[j+k]; j=i+2; //更新j n-=num; //数组减小num } i=j; //更新i } return n; } };
leetcode || 80、Remove Duplicates from Sorted Array II
原文地址:http://blog.csdn.net/hustyangju/article/details/44981085