Два отрезка

#include <stdio.h>
#include <conio.h>
 
float k_coeff(float x1, float y1, float x2, float y2);
float b_coeff(float x1, float y1, float x2, float y2);
void get_line(float &x1, float &y1, float &x2, float &y2);
 
void raschet();
 
int main()
{
    while(true)
    {
        raschet();
        printf("Press NUM 1 to enter new lines\r\n");
        if('1' != getch())
            break;
    }
    printf("Press any key to continue\r\n");
    getch();
    return 0;
}
 
void get_line(float &x1, float &y1, float &x2, float &y2)
{
    printf("Enter coordinates of strat x1,y1 and end of line x2,y2\r\n");
    printf("x1 = ");scanf("%g",&x1);
    printf("y1 = ");scanf("%g",&y1);
    printf("x2 = ");scanf("%g",&x2);
    printf("y2 = ");scanf("%g",&y2);
}
 
void raschet()
{
    float x1,x2,y1,y2,x3,y3,x4,y4,X,Y;
    printf("\t1-st line\r\n");
    get_line(x1, y1, x2, y2);
    printf("\t2-nd line\r\n");
    get_line(x3, y3, x4, y4);
 
    float k1 = k_coeff(x1, y1, x2, y2);
    float b1 = b_coeff(x1, y1, x2, y2);
 
    float k2 = k_coeff(x3, y3, x4, y4);
    float b2 = b_coeff(x3, y3, x4, y4);
 
    if(k1 != k2)
    {
        X = (b1 - b2)/(k2 - k1);
        Y = k1*X + b1;
        printf("\tCoordinates of cross-point\r\n");
        printf("O(%g;%g)\r\n",X,Y);
    }
}
 
float k_coeff(float x1, float y1, float x2, float y2)
{
    float k = 0;
    if(x1 != x2)
        k = (y2 - y1)/(x2 - x1);
    return k;
}
 
float b_coeff(float x1, float y1, float x2, float y2)
{
    float b = 0;
    if(x1 != x2)
        b = (y2*x1 - y1*x2)/(x1 - x2);
    return b;
}