Fractal Tree

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

double angle=(30*3.14)/180;
void fractal(int l,double a,int x,int y){
    if(l!=0){
        double a1=a+angle, a2=a-angle;

        int x1=x+l*cos(a1);   int y1=y-l*sin(a1);
        line(x,y,x1,y1);      fractal(l/2,a1,x1,y1);

        x1=x+l*cos(a2);       y1=y-l*sin(a2);
        line(x,y,x1,y1);      fractal(l/2,a2,x1,y1);

        a1=a1+angle;          a2=a2-angle;

        x1=x+l*cos(a1);       y1=y-l*sin(a1);
        line(x,y,x1,y1);      fractal(l/2,a1,x1,y1);

        x1=x+l*cos(a2);       y1=y-l*sin(a2);
        line(x,y,x1,y1);      fractal(l/2,a2,x1,y1);
    }
}

void main(){
    int gd=DETECT,gm;
    initgraph(&gd,&gm," ");
    fractal(100, (90*3.14)/180, 320, 400);
    getch();
    closegraph();
}