#Leetcode# 922. Sort Array By Parity II

https://leetcode.com/problems/sort-array-by-parity-ii/

Given an array A of non-negative integers, half of the integers in A are odd, and half of the integers are even.

Sort the array so that whenever A[i] is odd, i is odd; and whenever A[i]is even, i is even.

You may return any answer array that satisfies this condition.

Example 1:

Input: [4,2,5,7]
Output: [4,5,2,7]
Explanation: [4,7,2,5], [2,5,4,7], [2,7,4,5] would also have been accepted.

Note:

1. 2 <= A.length <= 20000
2. A.length % 2 == 0
3. 0 <= A[i] <= 1000

代码：

class Solution {
public:
    vector<int> sortArrayByParityII(vector<int>& A) {
        int n = A.size();
        vector<int> ans;
        vector<int> isodd; vector<int> nodd;
        for(int i = 0; i < n; i ++) {
            if(A[i] % 2) isodd.push_back(A[i]);
            else nodd.push_back(A[i]);
        }
        int a = isodd.size() - 1, b = nodd.size() - 1;
        for(int i = 0; i < n; i ++) {
            if(i % 2) {ans.push_back(isodd[a]); a --;}
            else {ans.push_back(nodd[b]); b --;}
        }
        return ans;
    }
};

　　这个题好无聊哦。。。