#include<stdio.h>

void swap(float *a,float *b) {
    float temp = *a;
    *a = *b;
    *b = temp;
}
int main() {
    float distance1, distance2;
    char ch;
    if(scanf("%f %f%c", &distance1, &distance2, &ch) !=2) {
        printf("Invalid input"); 
        return 0;
    }
    

    if(distance1 <-10000 || distance1 > 10000 || distance2 <-10000 || distance2 >10000){
        printf("Invalid input");
        return 0;
    }
    void(*swapPtr)(float*,float*) = swap;
    swapPtr(&distance1, &distance2);
    printf("After swap: Distance 1=%.0f meters\n", distance1"Distance 2 =%.0f  meters\n",distance2);
    return 0;
    
    
}