#include <iostream>
using namespace std;

int main() {
	int n;
	cin >> n;
	int arr[n];
	for(int i = 0; i < n; i++){
		cin >> arr[i];
	}
	for(int i = 1; i < n; i+=2){
		int q = arr[i];
		arr[i] = arr[i-1];
		arr[i-1] = q;
	}
	for(int i = 0; i < n; i++){
		cout << arr[i] << " ";
	}
	return 0;
}