#include <stdio.h>
void swap(int *a,int *b){
    int temp = *a;
    *a = *b;
    *b= temp;
}
int main(){
    int d1,  d2;
    if(scanf("%d %c",&d1,&ch ) !=2 || ch != '\n'){
        printf("Invalid input");
        return 0;
    }
    if (scanf("%d %c",&d2,&ch) !=2 || ch != '\n'){
        printf("Invalid input");
        return 0;
    }
    void (*fp)(int *, int *)= swap;
    fp(&d1,&d2);
    printf("After swap: Distance 1 = %d meters\n",d1);
    printf("Distance 2 = %d meters",d2);
    return 0;
}