very noob on c# assignment : ) need help (2d array)

cSharpDonkey

Hi, thanks for taking your time to read and maybe drop some knowledge -

Im making a console application that lets you order tickets for seats in the cinema.
I've been trying to make a 2d array to use for the seats, using 15 rows and 20 seats.
I can't make it work proberly and im wondering what's the better way to build this project -
here's some things i tried:

int[ , ] pladser = new int[15, 20];
for (int foo = 0; foo < pladser.GetLength(0); foo++ ) { for (int bar = 0; bar < pladser.GetLength(1); bar++){ pladser[foo, bar] = 1 + bar;
Console.Write(pladser[foo, bar]);
//when i write it this way the console dose not change row after last seat but writes all the 20 seats through 15 in a single line

int[,] pladser = new int[,]
{
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
};
int foo;
foo = Convert.ToInt32(pladser);
Console.WriteLine(foo);
//this gives me no error reports but wont write it proberly due to a system 32 message -

int[,] pladser = new int[,]
{
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
};
for (int x = 0; x < 15; x = x++)
{
for (int y = 0; y < 20; y = y++)
{

}
Console.Write(pladser[x, y]);
//this time i thought i finally had it but i got something wrong still and cant run the program.
//the name y does not exist - probably just an easy fix?
// Any ideas how i could get this project going would be much appreciated

14 Replies

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Vulpes13y ago
Accepted answer
OK, I've done most of that.

At the moment, if the user doesn't want to choose the seats individually, the seats are chosen completely at random as it's much more complicated to choose adjacent seats, particularly as the cinema fills up, though something like this can certainly be coded.

Also there's not much in the way of error checking as there's a lot of stuff that could potentially go wrong:

using System;

class Program
{
static ConsoleColor original;
static bool[,] chosen;
static int[,] pladser;
static Random rand = new Random();

static void Main()
{
// save console background color
original = Console.BackgroundColor;

chosen = new bool[15,20]; // all elements false initially

pladser = new int[15,20]
{
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
};

DisplaySeats();
Console.Write("\nHow many seats do you want to reserve : ");
int numSeats = int.Parse(Console.ReadLine());
Console.Write("How many of these are for adults : ");
int adults = int.Parse(Console.ReadLine());
int children = numSeats - adults;
Console.WriteLine("So number of children's seats : {0}", children);
Console.Write("Choose your seats individually y/n : ");
bool individual = Console.ReadLine().ToLower() == "y";
int[] row = new int[numSeats];
int[] col = new int[numSeats];

if (individual)
{
Console.Write("Enter row (max 15 and column (max 20) separated by a comma for each seat\n");
for(int i = 0; i < numSeats; i++)
{
Console.Write(" Seat {0, 2} : ", i + 1);
string input = Console.ReadLine();
string[] split = input.Split(',');
row[i] = int.Parse(split[0]) - 1;
col[i] = int.Parse(split[1]) - 1;
if (!chosen[row[i], col[i]])
{
chosen[row[i], col[i]] = true;
}
else
{
Console.WriteLine(" Sorry already reserved, please choose another seat");
i--;
}
}
}
else
{
for(int i = 0; i < numSeats; i++)
{
int r = rand.Next(0, 15);
int c = rand.Next(0, 20);
if (!chosen[r, c])
{
row[i] = r;
col[i] = c;
chosen[r, c] = true;
}
else
{
i--;
}
}
}

DisplaySeats();
ShowPrice(adults, children);
Console.ReadKey();
}

static void DisplaySeats()
{
Console.Clear();
Console.WriteLine("|----------------------------------CINEMA--------------------------------------|");

for (int foo = 0; foo < pladser.GetLength(0); foo++ )
{
for (int bar = 0; bar < pladser.GetLength(1); bar++)
{
pladser[foo, bar] = 1 + bar;

if (chosen[foo, bar])
Console.BackgroundColor = ConsoleColor.DarkRed;
else
Console.BackgroundColor = ConsoleColor.DarkGreen;

Console.Write("{0,3} ", pladser[foo, bar]);
}

}

Console.BackgroundColor = original;
}

static void ShowPrice(int adults, int children)
{
int price = 80 * adults + 40 * children;
Console.WriteLine("\nPrice of seats : {0} x 80 + {1} X 40 = {2} kr", adults, children, price);
}
}
Vulpes12y ago
As I've seen similar questions come up before, the final program may be of interest to other novice programmers so I'd .zip or. rar it and upload it to this thread.

Different people learn new stuff in different ways. Personally, I've always preferred books to online videos as you can learn at your own pace without having to stare at the screen for long periods of time.

There are many good books on learning C# programming including this one which is particularly good if you're wishing to concentrate on the language itself rather than its myriad applications:

http://www.amazon.co.uk/C-4-0-The-Complete-Reference/dp/007174116X/ref=pd_sim_sbs_b_2
cSharpDonkey12y ago
Okey i finished the program got alot of help, besides what you provided, if you are interested i can show you the program if u give me your email :) -
Also i wanna ask, what's a good way to get better at this, any advice?, tryed watching alot youtube guide's and read c# articles and books, any excercises or reading / video material you can recommend?
cSharpDonkey13y ago
Vulpes you are the biggest, baddest programmer, i liked your profile and thumbs up on your comments, i hope this helps you in anyway - i will try working with all this and get back to this thread ASAP - Thanks alot
sincerely: c#Donkey
cSharpDonkey13y ago
Ahh isee now, i was missing the initial DisplaySeats(); I now added this, and tried moving around the later one to try the different options, this is very awesome and you are truly a big help, you make it alot clearer for me!
- Is it possible to a function to the Seat picking phase that lets user choose wether he/she wants to pick their own seats, or declare number of seats and then use Random to pick the number of seats anywhere currently available?(maybe even any X seats NEXT to eachother available)
and then add a function that lets the user say how many childs/adults for different prices -
so that the final price for all the tickets shows as the seats are reserved and turned red-
- please bare with me im eager to learn and get this working
Vulpes13y ago
If you put it where I've put it, then the seats will be displayed (all green initially, of course) when the user is asked to make his/her reservations.

If you want the seats to be re-displayed after each seat is reserved - rather than when all the reservations have been made - then just move the final DisplaySeats() so that it's the last line in the for statement.
cSharpDonkey13y ago
How do i know where to put it in the program?
- can i do it vise versa so the user can get a look at which seets are free and which are avaible first?

or maybe so the input / output user vs program happens below the array so u can watch seats while you are using it?
Vulpes13y ago
You're thinking on the right lines but it needs some work to get it to compile.

Try the highlighted code:

using System;

class Program
{
static ConsoleColor original;
static bool[,] chosen;
static int[,] pladser;

static void Main()
{
// save console background color
original = Console.BackgroundColor;

chosen = new bool[15,20]; // all elements false initially

pladser = new int[15,20]
{
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
};

DisplaySeats();
Console.Write("\nHow many seats do you want to reserve : ");
int numSeats = int.Parse(Console.ReadLine());
Console.Write("Enter row (max 15 and column (max 20) separated by a comma for each seat\n");
int[] row = new int[numSeats];
int[] col = new int[numSeats];

for(int i = 0; i < numSeats; i++)
{
Console.Write(" Seat {0, 2} : ", i + 1);
string input = Console.ReadLine();
string[] split = input.Split(',');
row[i] = int.Parse(split[0]);
col[i] = int.Parse(split[1]);
chosen[row[i] - 1, col[i] - 1] = true;
}

DisplaySeats();
Console.ReadKey();
}

static void DisplaySeats()
{
Console.Clear();
Console.WriteLine("|----------------------------------CINEMA--------------------------------------|");

for (int foo = 0; foo < pladser.GetLength(0); foo++ )
{
for (int bar = 0; bar < pladser.GetLength(1); bar++)
{
pladser[foo, bar] = 1 + bar;

if (chosen[foo, bar])
Console.BackgroundColor = ConsoleColor.DarkRed;
else
Console.BackgroundColor = ConsoleColor.DarkGreen;

Console.Write("{0,3} ", pladser[foo, bar]);
}

}

Console.BackgroundColor = original;
}
}
cSharpDonkey13y ago

Hi Vulpes, this idea sounds very viable and logical.
my problem is i don't know how to get it started, and i'm having a hard time navigating through this foreign language of c#..

i have gone with your new way to build the program, i see what you are saying that its better to build it this way, i think i understand the theory behind this, but not in practise.

next step for me is to let the user choose a number of specific seats to reserve them, and color them red - rather then the preset 3 red seats you made for an example -
how can i pull this info from user to program, and use it ?

here is something i tried, i just wanted to try and write something and im aware this code wont work or run, but i hope you see my idea here

string rowSeat[,]; //declaring string for the user to chose [,] correct row and seat
string userRow; //declaring string for users row
Console.WriteLine("please write row number");
userRow = (Console.ReadLine()); //convert string to int 32
userRow1 = userRow--; //minus 1 to get the correct row in array

string userSeat; //declaring string for seat nr
Console.WriteLine("please write seat number");
userSeat = (Console.ReadLine());
userSeat1 = userSeat--;
rowSeat[userSeat, userRow];
chosen = rowSeat[,] true
Vulpes13y ago
Well, I'd create a 2-D array of bool to store whether each seat is chosen or not.

I'd also move the code to show the seats (including the appropriate colors) to a separate method as you'll need to call it each time a seat is chosen or 'unchosen'.

The code will now look something like this:

using System;

class Program
{
static ConsoleColor original;
static bool[,] chosen;
static int[,] pladser;

static void Main()
{
// save console background color
original = Console.BackgroundColor;

chosen = new bool[15,20]; // all elements false initially

// choose a few at random
chosen[1, 5] = true;
chosen[2, 7] = true;
chosen[10,10] = true;

pladser = new int[15,20]
{
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
};

DisplaySeats();
Console.ReadKey();
}

static void DisplaySeats()
{
Console.Clear();
Console.WriteLine("|----------------------------------CINEMA--------------------------------------|");

for (int foo = 0; foo < pladser.GetLength(0); foo++ )
{
for (int bar = 0; bar < pladser.GetLength(1); bar++)
{
pladser[foo, bar] = 1 + bar;

if (chosen[foo, bar])
Console.BackgroundColor = ConsoleColor.DarkRed;
else
Console.BackgroundColor = ConsoleColor.DarkGreen;

Console.Write("{0,3} ", pladser[foo, bar]);
}

}

Console.BackgroundColor = original;
}
}
cSharpDonkey13y ago
Console.WriteLine("|--------------------------CINEMA--------------------------|\n");
int[,] pladser = new int[,]
{
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
};

for (int x = 0; x < pladser.GetLength(0); x++)
{
for (int y = 0; y < pladser.GetLength(1); y++)
{
Console.Write("{0,3}",pladser[x, y]);

}
Console.WriteLine();

}

}
}
}
Thanks - jaganatha and vulpes, my program is now runnable, and i've added the spaces in between items in the array thanks to your replie vulpes -

Here is when it gets tricky, i now wanna add a green background color to my seats if they are available, and red when they get chosen in program, how should i start doing this?.
I Believe im looking for some if / else statements? - any better ideas?
any critism, ideas, or general thoughts much appreciated !
Vulpes13y ago
This code is working OK for me:

using System;

class Program
{
static void Main()
{
int[,] pladser = new int[15,20]
{
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20},
};

for (int foo = 0; foo < pladser.GetLength(0); foo++ )
{
for (int bar = 0; bar < pladser.GetLength(1); bar++)
{
pladser[foo, bar] = 1 + bar;
Console.Write("{0,2} ", pladser[foo, bar]);
}

Console.WriteLine();
}

Console.ReadKey();
}
}

The output is:

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
cSharpDonkey13y ago
I now edited the for loops abit as you said, and added the writeline,
for some reason thought, it writes 15x15 seats not the 15x20 intended
Jaganathan Bantheswaran13y ago
Try like this,

for (int foo = 0; foo < pladser.GetLength(0); foo++ )
{
for (int bar = 0; bar < pladser.GetLength(1); bar++)
{
Console.Write(pladser[foo, bar]);
}
Console.WriteLine();
}