#include<stdio.h>
void swap(int *a, int *b){
    int temp = *a;
    *a = *b;
    *b = temp;
}
int main()
{
    int x,y;
    scanf("%d",&x);
    scanf("%d",&y);
    if(x<0&&y<0){
        printf("Invalid input\n");
        return 0;
    }
    swap(&x,&y);
    printf("%d\n%\n",x,y);
}