#include <stdio.h>
#include <math.h>


int main()
{
    double x0, y0, x1, y1, x2, y2, dist01, dist02, dist12;
    extern double dist(double x0, double y0, double x1, double y1);

    printf("Enter x and y values for point #0: ");
    scanf("%lg%lg", &x0, &y0);
    printf("Enter x and y values for point #1: ");
    scanf("%lg%lg", &x1, &y1);
    printf("Enter x and y values for point #2: ");
    scanf("%lg%lg", &x2, &y2);

    dist01 = dist(x0, y0, x1, y1);
    dist02 = dist(x0, y0, x2, y2);
    dist12 = dist(x1, y1, x2, y2);

    if (dist01 < dist02 && dist01 < dist12)
	printf("Points 0 and 1 are closest together\n");
    else if (dist02 < dist12)
	printf("Points 0 and 2 are closest together\n");
    else
	printf("Points 1 and 2 are closest together\n");

    return 0;
}


double dist(double x0, double y0, double x1, double y1)
{
    return sqrt((x0-x1) * (x0-x1) + (y0-y1) * (y0-y1));
}