Bresenham

#include<stdio.h>
#include<math.h>
#include<conio.h>
#include<graphics.h>
#include<time.h>

int main()
{
    int gd=DETECT,gm;
    initgraph (&gd,&gm,"");
    int x, y, x1, y1, x2, y2, dx, dy, step, p;
    int i;

    printf("Enter x1 and y1:\n");
    scanf ("%d %d", &x1, &y1);

    printf("Enter x2 and y2:\n");
    scanf ("%d %d", &x2, &y2);

    dx = (x2 - x1);
    dy = (y2 - y1);

    printf("%d %d \n", dx, dy);

    step = dx;

    p = (2*dy - dx);

    x = x1;
    y = y1;

    printf("Values of x and y:\n ");

    for(i = 1;i <= step; i++)

    {
            if(p < 0)
    {
        x++;
        p = p + 2 * dy;
    }

    else{
        x++;
        y++;
        p = p + 2 * dy - 2 * dx;
    }
         printf("%d %d \n", x ,y);
         putpixel(round(x) , round(y),WHITE);
        delay(10);
    }
     getch();
     closegraph();
    }