class Main{
java.
util.
Scanner i
= new java.
util.
Scanner(System.
in); int n = i.nextInt();
int arr[] = new int[n];
for(int k = 0; k < n; k++){
arr[k] = i.nextInt();
}
for(int k = 1; k < n; k+=2){
int q = arr[k];
arr[k] = arr[k-1];
arr[k-1] = q;
}
for(int k = 0; k < n; k++){
System.
out.
print(arr
[k
] + " "); }
}
}
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