two dimensional arrays!

[Thuraya]

Hi,

if I have numbers in 9X9 board/grid ,
the choice is to user whether to bring the numbers from a file or enter his numbers.

Then the program should display the 9x9 board as a two dimensional board.

how to do this part?

[Mohamed Fouad]

That could be done like this:

#include<iostream>
#include<fstream>

using namespace std;

int input(istream& in=cin)
{
	int x;
	in >> x;
	return x;
}

int main()
{
	int board[9][9]; //creates a 9*9 matrix or a 2d array.

	for(int i=0; i<9; i++)    //This loops on the rows.
	{
		for(int j=0; j<9; j++) //This loops on the columns
		{
			board[i][j] = input(); //you can also connect to the file
			//and place the name of your ifstream in the input after opening the file will
			//let you read from the file.
		}
	}

	for(int i=0; i<9; i++)    //This loops on the rows.
	{
		for(int j=0; j<9; j++) //This loops on the columns
		{
			cout << board[i][j]  << "  ";
		}
		cout << endl;
	}
}

Input example:

1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9

Output example:

1  2  3  4  5  6  7  8  9  
1  2  3  4  5  6  7  8  9  
1  2  3  4  5  6  7  8  9  
1  2  3  4  5  6  7  8  9  
1  2  3  4  5  6  7  8  9  
1  2  3  4  5  6  7  8  9  
1  2  3  4  5  6  7  8  9  
1  2  3  4  5  6  7  8  9  
1  2  3  4  5  6  7  8  9  

[Thuraya]

OK if the file have the numbers as your output example order or the user entered them in that order, I mean (9 lines each line have 9 values)

then will the two dimensional array be useless ?

[Mohamed Fouad]

The user entered 81 elements I stored them in a 2d array board[9][9] then I output first row then a new line then second row and then a new line and so on.

[Mohamed Fouad]

Look again here:

for(int i=0; i<9; i++)    //This loops on the rows.
	{
		for(int j=0; j<9; j++) //This loops on the columns
		{
			cout << board[i][j]  << "  ";
		}
		cout << endl;
	}

After the elements have been stored the two for loops in the first iteration will out put the element board[0][0] which is first then increment the j so it will output board[0][1] and so on till it reaches the end if 1st row in the 2d array then I print a new line then increment the i to output board[1][0] (1st element in the 2nd row) the increment the j to reach the end of the second row and so in

[Thuraya]

yeah but what I mean is that when I ask the user to enter 9x9 numbers (9 lines each line contains 9 numbers) from the beginning.

like this problem:
Write a C++ program that reads numbers into a 9x9 board/grid. The program should give the user the option to get the numbers from a file (and give the file name to the program) or via the key board. The input file should have the numbers stored in 9x9 grid (9 lines with 9 values on each line).

The program should check if any number entered is not suitable for the game (numbers which are allowed are integers from 1 to 9).

The program should then display the 9x9 board as a two dimensional board.

The program should check whether the 9x9 board configuration is a successful Sudoku configuration; i.e., each row, each column and each of the nine 3×3 sub-grids contains exactly one of the digits from 1 to 9. The following is an example of a successful Sudoku configuration.

[Mohamed Fouad]

Put this code in your IDE and input this

1  2  3  4  5  6  7  8  9  
1  2  3  4  5  6  7  8  9  
1  2  3  4  5  6  7  8  9  
1  2  3  4  5  6  7  8  9  
1  2  3  4  5  6  7  8  9  
1  2  3  4  5  6  7  8  9  
1  2  3  4  5  6  7  8  9  
1  2  3  4  5  6  7  8  9  
1  2  3  4  5  6  7  8  9

Will also work and pit it in a file connect ifstream to that file and put the name of the stream in the function input then close the file at the end of the program will also work!

[GodPyro]

@Thuraya If you use infile >> number; Shouldn't matter which way you enter it in the file. Whether it is in a single line or structured like the output.

[Mohamed Fouad]

Yes this is correct but before calling the finction input make sure that you have this in your code

ifstream fin;
fin.open("input.txt"); //Or any [code]name your file has.
input(fin);

//After finishing with the function call don't forget to close the file
fin.close();

Also don't forget to #include<fstream>

[Thuraya]

Thanks I've done every thing ,
,
One more lil Question,

How Can I check 2D array ?

Here e.g :

if (board[9][9]>=1 && board[9][9]<=9)

cout << "The Numbers are Suitable" << endl;

else

cout << "The Numbers are NOT suitable" << endl;

I did this but it always give me the second answer , !!!! But my numbers are all from 1-9

[GodPyro]

You have to place your conditionals in a nested for loop.

for(int i = 0; i < 9; i++)
{
    for(int j = 0; j < 9; j++)
    {
        if (board[i][j]>=1 && board[i][j]<=9)
            cout << "The Numbers are Suitable" << endl; 
        else 
            cout << "The Numbers are NOT suitable" << endl;
    }
}

[Thuraya]

But , I don't want the sentence to be repeated !!
BTW, it gives me the correct checking but ,(repeating thing is left)!

how to do it ?

[Mohamed Fouad]

This can easily be done by:

#include<iostream>
#include<fstream>

using namespace std;

int input(istream& in=cin)
{
	int x;
	in >> x;
	return x;
}

int main()
{
	int board[9][9]; //creates a 9*9 matrix or a 2d array.
        
	/////////////////////////////////////////////////////////////////
	//Here is a new part.
	/////////////////////////////////////////////////////////////////
	//New boolean expression intialized to false.
	bool isSuitable = false;

	for(int i=0; i<9; i++)    //This loops on the rows.
	{
		for(int j=0; j<9; j++) //This loops on the columns
		{
			board[i][j] = input(); //you can also connect to the file
			//and place the name of your ifstream in the input after opening the file will
			//let you read from the file.

		}
	}

	/////////////////////////////////////////////////////////////////
	//Here is a new part.
	/////////////////////////////////////////////////////////////////


	for(int i=0; i<9; i++)    //This loops on the rows.
	{
		for(int j=0; j<9; j++) //This loops on the columns
		{
			if(board[i][j]>=1 && board[i][j]<=9)
				isSuitable = true;
			else
			{
				isSuitable = false;
				break;
			}
		}
		if(isSuitable == false)
			break;
	}



	for(int i=0; i<9; i++)    //This loops on the rows.
	{
		for(int j=0; j<9; j++) //This loops on the columns
		{
			cout << board[i][j]  << "  ";
		}
		cout << endl;
	}


	////////////////////////////////////////////////////////////////
	//Here is also a new part.
	////////////////////////////////////////////////////////////////
	if (isSuitable)
		cout << "The Numbers are Suitable" << endl;
	else
        cout << "The Numbers are NOT suitable" << endl;

}

[Thuraya]

many errors appear !!

please help me I need to solve it today :!

[GodPyro]

What are the errors?

[Mohamed Fouad]

Sorry add a return 0; at line 74 before the closing brace and if you use DEV CPP add a system("PAUSE"); before the return 0;

[Thuraya]

, thanks It works

If I want to check each column and row to contain only one digit from (1-9)
here my code:

//a function to check the rows and columns 
void col_row(int sudok[][9],int siz)
{
    bool duplic = false;
	for(int i=0;i<siz;i++)
	{
		for(int j=0;j<siz;j++)
		{
			if(sudok[i]!= sudok[i+1])
				duplic = true;
			else
			{duplic = false;
			break;
			}
		}
		if(duplic == false)
			break;

	}
 if(duplic)
	 cout << "The Numbers are suitable for the game" << endl;
 else
	 cout << "The Numbers are Not good for the game" << endl;
}

but it doesn't do what I want ,It gives random numbers after the array and then the program stop working .. !!!