c++ program to find the steps in order to attack enemies

Program to find the steps in order to attack enemies

Game development requires a lot of mathematics, physics, and algorithms, so to practice
with
CPP in a fun way it can be helpful that you solve problems related to the game. I really enjoy game programming that's why I'm writing this post.

The program that we're going to write is not so hard, it's simple, easy and better for you if you're a beginner programmer in CPP.

Read my another post

• Vector and 3x3 matrix implementation
• Fibonacci series in c++
• java game development series

Two Dimensional Vector structure

You better know that to represent the position of any object or point in
the 2D
coordinate-system we use vectors that start from (0,0) and end at position P(x,y). So first, we have to implement a 2d Vector before we can use it in our program.

To implement a Vector we can
use either CPP's struct or class, both are
same but they are different by default properties that are a struct
contains public member by default and a class contains private
members.

I'm using the struct to
implement a vector structure named as
Vector2D

(see the code snippet
below).

Code snippet

struct Vector2D
{
    float x, y; // 1

    Vector2D() = default; // 2
    Vector2D(float a, float b) // 3
    {
    x = a;
    y = b;
    }

/****************
* Vector Operations *
*****************/

    Vector2D& operator += (const Vector2D& velocity)
    {
    x += velocity.x;
    y += velocity.y;
    return *this;
    }

                            
                    
    Vector2D& operator -= (const Vector2D& velocity)
    {
    x -= velocity.x;
    y -= velocity.y;
    return *this;
    }

    Vector2D operator + (const Vector2D& velocity) const
    {
    return Vector2D(x+velocity.x, y+velocity.y);
    }

                            
                    
    Vector2D operator - (const Vector2D& velocity) const
    {
    return Vector2D( x - velocity.x, y - velocity.y );
    }
};

1. Inside the Vector2D
   float x,y represents x and y
   coordinate,

2. Vector2D() is marked as
   a default constructor.

3. and there is another
   constructor which accepts a, strong values, assign
   them to x,y.

4. This is enough to represent a 2d vector.

5. but we want to do some operations on them such as addition,
   subtraction, and multiplication of two vectors. To do so I implement some operator overload
   functions.

Yeah, we've done this! Now we can easily use Vector objects in the
program.

Q.How to reach to the
enemy?

To better understand what we're going to do See the above image, Player P
and enemy E is at 4, 4, and 13, 6 respectively, and in order to attack the
Enemy Player P should go some steps to right and up. It is simple to
calculate these steps, we have to just subtract vector P(4, 4) from E(13, 6)
then we get vector d(9, 2) means that Player p should go 9 steps to the right
and 2 steps to up to attack the enemy.

#include <iostream>

int main() {
    float x, y;

    std::cout << " Position of the Player--> " << std::endl;

    std::cin >> x;

    std::cin >> y;

    Vector2D p(x, y);

    std::cout << " Position of the Enemy--> " << std::endl;

    std::cin >> x;

    std::cin >> y;

    Vector2D e(x, y);

    e -= p;

    std::cout << "Player
    should move " << e.x << "
    times right and "

    <<
    e.y << " times
    up to attack " << std::endl;

    system("pause");

    return 0;

}