# include<iostream> using namespace std; int a[101]; int main(){ int n; cin>>n; for(int i=1;i<=n;i++){ cin >>a[i]; } int p; for (int i=1;i<n;i+2){ p=a[i]; a[i]=a[i+1]; a[i+1]=p; } for (int i=0;i<=n;i++){ cout <<a[i]<<" "; } return 0; }