大佬答案

#include<iostream>
#include<vector>
using namespace std;

template<typename T>
ostream& operator<<(ostream& os,vector<T>& vec){
    for (T ele:vec) os << ele << ' ';
    os << endl;
    return os;
}

vector<int>evens,odds;
int main(){
    int n, element;
    cin >> n;
    while(n--){
        cin >> element;
        (element%2) ? odds.push_back(element) : evens.push_back(element);
    }
    cout << evens << odds;
    return 0;
}