#include<bits/stdc++.h> using namespace std; int a[105]; int main(){ int n; cin>>n; for(int i = 1;i <= n;i++){ cin>>a[i]; } for(int i = 1;i < n;i+=2){ int t = a[i]; a[i] = a[i+1]; a[i+1] = t; } for(int i = 1;i <= n;i++){ cout<<a[i]<<" "; } return 0; }