#include<iostream> // cin\cout\endl #include<cstdio> //scanf()\printf() #include<cstring> // strcpy()\strcat()\strcmp()\strlen()\memset() #include<cmath> //sqrt()\pow()\abs()\ceil()\floor()\max()\min() using namespace std; int main(){ int a[100],n,t; cin>>n; for(int i=1;i<=n;i++) cin>>a[i]; 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]<<" "; cout<<a[n]<<endl; return 0; }