#include <stdio.h>
 int main(){
     int n,a[100],i,t;
     
     scanf("%d",&n);
     
     for(i = 0; i < n; i++)
     scanf("%d",&a[i]);
     
     for(i = 0;i < n-1;i +=2){
         t = a[j];
         a[i]= a[i+1];
         a[i+1]=t;
     }
     for(i = 0;i < n; i++)
     printf("%d",a[i]);
     
     return 0;
 }