piece of code does not work

saman hamidi

Why does this piece of code does not work?
it is supposed to be a "random walk". and I should not be using any methods or classes. just branching, looping and arrays.
I have no errors from the compiler but when I try to run the code console appears and then disappears before I can do anything.

static void Main(string[] args)
        {
            Random randomObject = new Random();
            int randomDirection;
            int row=1;
            int col=1;
            while (true)
            {
                int n;
                int row = 1;
                int col = 1;
                Console.WriteLine("Enter the number of steps: ");
                n = Convert.ToInt32(Console.ReadLine());
                for (int i = 0; i < n; i++)
                {
                    randomDirection = randomObject.Next(1, 5);
                    if (randomDirection == 1 && row > 0 && row < 10)
                        row++;
                    else if (randomDirection == 2 && row > 0 && row < 10)
                        row--;
                    else if (randomDirection == 3 && col > 0 && col < 10)
                        col++;
                    else if (randomDirection == 4 && col > 0 && col < 10)
                        col--;
                    else
                        i--;
                }
                Console.WriteLine("You have walked in row: " + row);
                Console.WriteLine("You have walked in col: " + col);
                Console.WriteLine("");
            }
            Console.ReadKey();
        }

4 Replies

Know the answer? Post it — somebody with the same question will find it here.

Srinubabu Ravilla13y ago
Accepted answer
I have tried it. Please remove the local variable row and col and then try it as follows.

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

namespace ConsoleApplication1

{

    class Program

    {

        static void Main(string[] args)

        {

            Random randomObject = new Random();

            int randomDirection;

            int row = 1;

            int col = 1;

            while (true)

            {

                int n;

                Console.WriteLine("Enter the number of steps: ");

                n = Convert.ToInt32(Console.ReadLine());

                for (int i = 0; i < n; i++)

                {

                    randomDirection = randomObject.Next(1, 5);

                    if (randomDirection == 1 && row > 0 && row < 10)

                        row++;

                    else if (randomDirection == 2 && row > 0 && row < 10)

                        row--;

                    else if (randomDirection == 3 && col > 0 && col < 10)

                        col++;

                    else if (randomDirection == 4 && col > 0 && col < 10)

                        col--;

                    else

                        i--;

                }

                Console.WriteLine("You have walked in row: " + row);

                Console.WriteLine("You have walked in col: " + col);

                Console.WriteLine("");

            }

            Console.ReadKey();

        }

    }

}
Jignesh Trivedi13y ago
hi,

I have also got completion error on above code.

A local variable named 'row' cannot be declared in this scope because it would give a different meaning to 'row',
which is already used in a 'parent or current' scope to denote something
else

if we remove int declaration from row and col than it work fine.

Random randomObject = new Random();
int randomDirection;
int row = 1;
int col = 1;
while (true)
{
    int n;
    row = 1;
    col = 1;
    Console.WriteLine("Enter the number of steps: ");
    n = Convert.ToInt32(Console.ReadLine());
    for (int i22 = 0; i22 < n; i22++)
    {
        randomDirection = randomObject.Next(1, 5);
        if (randomDirection == 1 && row > 0 && row < 10)
            row++;
        else if (randomDirection == 2 && row > 0 && row < 10)
            row--;
        else if (randomDirection == 3 && col > 0 && col < 10)
            col++;
        else if (randomDirection == 4 && col > 0 && col < 10)
            col--;
        else
            i22--;
    }
    Console.WriteLine("You have walked in row: " + row);
    Console.WriteLine("You have walked in col: " + col);
    Console.WriteLine("");
}
Console.ReadKey();
saman hamidi13y ago
I did what you said. but it still doesn't work. the console shows and then disappears. could you please tell why this happens?
Javeed M Shaikh13y ago
I see a compiler error in your code:

while (true)
            {
                int n;
                int row = 1;
                int col = 1;

you have already declared int row and int col above this loop, change it to:

while (true)
            {
                int n;
row = 1;
col = 1;