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