A simple sinking ship game with C++

[Kew]

i am trying to create a simple game with C++, but i meet some bug when running the game. First thing will be the random position generated. It is not always correct. Sometime i want 5 ships for total, but it give me 4 ships. Can anyone tell me what is the problem?

#include <iostream>
#include <cstdlib>

using namespace std;

const int row = 5;
const int element = 5;
int matrix[row][element];

void set();
//Set the matrix[row][element] = 0

void setShip(int maxShip);
// Generate a random position for the ship, and set the position = 1

void show();
// show the matrix on the screen

void attack(int& numberShip);
//Obtain a position (x,y) from the player for attacking
//if success, return "U got me"
//else, return "Fail"

void surrender(int& numberShip);
//Ask the player to surrender
//If player enter 'y' or 'Y', exit the game 

void clearScreen();
//Clear the screen.


int main()
{
	int maxShip;

	cout << "Enter the number of ship: ";

	cin >> maxShip;

	int numberShip = maxShip;

	set();
	setShip(maxShip);	
	show();
	attack(numberShip);

	return 0;
}

void set()
{
	for(int y = 0; y < element; y++)
		for(int x = 0; x < row; x++)
			matrix[y][x] = 0;

}

void setShip(int maxShip)
{
	int ry, rx;
	
	srand(time(0));
	
	do
	{
		ry = rand()%row;
		rx = rand()%element;

		matrix[ry][rx] = 1;

		maxShip--;
	}while(maxShip != 0);

}

void show()
{
	for(int y = 0; y < element; y++)
	{
		for(int x = 0; x < row; x++)
			cout << matrix[y][x] << " ";
		cout << endl;
	}
	cout << "---------------------------------\n";
}

void attack(int& numberShip)
{
	int x, y;

	
	while(numberShip != 0)
	{
		cout << "Please enter a position to attack :";
		cin >> x >> y;

		if(matrix[y-1][x-1] == 1)
		{
			clearScreen();
			cout << "You got me >,<\n";
			numberShip--;
			cout << "Number of ship remain :" << numberShip << endl;
			matrix[y-1][x-1] = 2;
			show();
		}
		else
		{
			cout << "You missed XD";
			surrender(numberShip);
		}

		
	}

	cout << "You win :(\n";
}

void surrender(int& numberShip)
{
	cout << " surrender?(Y/N)";

	char a;

	cin >> a;

	if(a == 'Y' || a == 'y')
	{
		exit(1);
	}
	else
	{
		clearScreen();
		show();
		attack(numberShip);
	}
}

void clearScreen()
{
	int index = 0;

	for(; index <100;index ++)
	{
		cout << "\n";
	}
}

[Peter87]

When you generate the ship positions you don't check if there is already a ship there.

[TheKingOfTyrants]

You're randomly generating a ship's position. This means that you can technically randomly generate the same position, but you don't check to make sure that maxtrix[rx][ry] is already occupied.

[Kew]

void setShip(int maxShip)
{
	int ry, rx;
	
	srand(time(0));
	
	do
	{
		ry = rand()%row;
		rx = rand()%element;

		if(matrix[ry][rx] == 0)
		{
				matrix[ry][rx] = 1;
				maxShip--;
		}		
			
	}while(maxShip != 0);

}

i had edited my function into this, but it still give me the same result?