# Determine whether a point is inside a rectangle

## Given a rectangle with four vertices in the cartesian rectangular coordinates. Write a program to determine whether a given point lies inside the rectangle, or outside it.

Last Reviewed and Updated on August 18, 2019

## C++ Program for Hit Testing. Determine whether a point is inside a rectangle.

P, Q, R and S are vertices of a rectangle in a clockwise cyclic order. The axes are cartesian where x is positive to the right, y is positive upwards. The coordinates of P are: (-6.1f, -4.3f), Q: (-6.1f, +4.3f), R: (+6.1f, +4.3f) and S: (+6.1f, -4.3f). Ask the user to enter the coordinates of a point of his choice. Write code to determine whether that point lies inside the rectangle or not. You have to model the problem into a C program. Test this program by entering x as 0.0 and y as 0.0. If your code is correct, the output would be: "Yes, inside!".

```#include <iostream>

using namespace std;

int main()
{
// points are cyclic
float PX = -6.1f, PY = -4.3f;
float QX = -6.1f, QY = +4.3f;
float RX = +6.1f, RY = +4.3f;
float SX = +6.1f, SY = -4.3f;

float x, y;

cout << "Enter x-coord: ";
cin >> x;

cout << "Enter y-coord: ";
cin >> y;

/*

Q___________________R
|                   |
|                   |
|                   |
|                   |
P___________________S

*/

if(
(y < QY)
&&
(y > PY)
&&
(x < RX)
&&
(x > QX)
)
{
cout << "Yes, Inside!" << endl;
}
else
{
cout << "Outside" << endl;
}

return 0;
}```

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Updated on 2019-08-18.