#include <stdio.h>
#include <math.h>
 
struct Coordinate {
    double x;
    double y;
    double z;
};
 
int main() {
    struct Coordinate a = {1, 5, 2};
    struct Coordinate b = {5, 3, 1};
    struct Coordinate c = {2, 8, 4};
 
    double length_ab = sqrt((b.x - a.x)*(b.x - a.x) +
                            (b.y - a.y)*(b.y - a.y) +
                            (b.z - a.z)*(b.z - a.z));
 
    double length_co = sqrt(c.x*c.x + c.y*c.y + c.z*c.z);
 
    printf("Length AB: %f\n", length_ab);
    printf("Length CO: %f\n", length_co);
 
    return 0;
}
 

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