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