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