#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");
        return o;
    }
    
    swap(&x, &y);
    
    printf("%d" "%d", x, y);
    
    return 0;
}