#include <bits/stdc++.h>
#include<graphics.h>
using namespace std;

// Defining region codes
const int INSIDE = 0;
const int LEFT = 1;
const int RIGHT = 2;
const int BOTTOM = 4;
const int TOP = 8;

 int x_max;
 int y_max;
 int x_min;
 int y_min;
int computeCode(double x, double y)
{
    int code = INSIDE;

    if (x < x_min)
        code |= LEFT;
    else if (x > x_max)
        code |= RIGHT;
    if (y < y_min)
        code |= BOTTOM;
    else if (y > y_max)
        code |= TOP;

    return code;
}
  void drawwindow()
{

	line(x_min,y_min,x_max,y_min);
	line(x_min,y_min,x_min,y_max);
	line(x_max,y_min,x_max,y_max);
	line(x_min,y_max,x_max,y_max);
}
void Clip(double x1, double y1, double x2, double y2)
{

    int code1 = computeCode(x1, y1);

     int code2 = computeCode(x2, y2);
     if(code1==0&&code2==0)
     {
         line(x1,y1,x2,y2);
     }

    bool accept = false;

    while (true)
    {
        if ((code1 == 0) && (code2 == 0))
        {
            accept = true;
            break;
        }
        else if (code1 & code2)
        {
            break;
        }
        else
        {
            int code_out;
            double x, y;
            if (code1 != 0)
                code_out = code1;
            else
                code_out = code2;
            if (code_out & TOP)
            {
                x = x1 + (x2 - x1) * (y_max - y1) / (y2 - y1);
                y = y_max;
            }
            else if (code_out & BOTTOM)
            {
                x = x1 + (x2 - x1) * (y_min - y1) / (y2 - y1);
                y = y_min;
            }
            else if (code_out & RIGHT)
            {
                y = y1 + (y2 - y1) * (x_max - x1) / (x2 - x1);
                x = x_max;
            }
            else if (code_out & LEFT)
            {
                y = y1 + (y2 - y1) * (x_min - x1) / (x2 - x1);
                x = x_min;
            }
            if (code_out == code1)
            {
                x1 = x;
                y1 = y;
                code1 = computeCode(x1, y1);
            }
            else
            {
                x2 = x;
                y2 = y;
                code2 = computeCode(x2, y2);
            }
        }
    }
    if (accept)
    {
        line(x1,y1,x2,y2);
    }

}

int main()
{
    cout<<"ENTER XMIN YMIN :"<<endl;
    cin>>x_min>>y_min;
    cout<<"ENTER XMAX YMAX :"<<endl;
    cin>>x_max>>y_max;
    cout<<"Enter No of Points "<<endl;
    int n;
    cin>>n;
    vector<pair<int,int> >v1;

    for(int i=1;i<=n;i++)
    {
        cout<<"Input x"<<i<<" y"<<i<<": ";
        int x1,y1;
        cin>>x1>>y1;
        v1.push_back({x1,y1});
    }
    int gd=DETECT,v,gm;
    initgraph(&gd,&gm,"");
    drawwindow();
    for(int i=1;i<n;i++)
    {
          int a=v1[i].first;
          int b=v1[i].second;
          int c=v1[i-1].first;
          int d=v1[i-1].second;
          Clip(a, b, c, d);

    }
          int a=v1[0].first;
          int b=v1[0].second;
          int c=v1[n-1].first;
          int d=v1[n-1].second;
          Clip(a, b, c, d);



          getch();
        closegraph();



    return 0;
}