#include <stdio.h>
#include <math.h>
int main () {
    volatile float a, b, c, p, s, x1, x2, x3, y1, y2, y3;
    x1 = 0.0; y1 = 0.0;
    x2 = 21.0; y2 = 34.0;
    x3 = 34.0; y3 = 55.0;
    a = hypot (y2 - y1, x2 - x1);
    b = hypot (y3 - y2, x3 - x2);
    c = hypot (y1 - y3, x1 - x3);
    p = (a + b + c) * 0.5;
    s = p * (p - a) * (p - b) * (p - c);
    s = sqrt (s);
    printf ("%.9f %.9f %.9f %.9f\n%.9f\n", a, b, c, p, s);
    return 0;
}