#include <bits/stdc++.h> using namespace std; int a[101]; int main () { int n; cin>>n; for(int i = 1; i<=n; i++) { cin>>a[i]; } int t; 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; }