#include<iostream> #include<cstdio> //scanf()\printf() #include<cstring> #include<cmath> //sqrt()\pow()\abs()\ceil()\floor()\max()\min() using namespace std; int main(){ int n,a[1001],t; cin>>n; for(int i=0;i<n;i++){ cin>>a[i]; } for(int i=0;i<n-1;i+=2){ t=a[i]; a[i]=a[i+1]; a[i+1]=t; } for(int i=0;i<n;i++){ cout<<a[i]<<' '; } return 0; }