#include<bits/stdc++.h>
using namespace std;
int main(){
    vector<int> v = {1,2,3,4,5};
    for(auto it=v.begin();it!=v.end();++it){
        cout<<*it<<" ";
    }
    cout<<"\n";
    for(auto it=v.rbegin();it!=v.rend();++it){
        cout<<*it<<" ";
    }
    cout<<"\n";
}