can't convert readline to int32

Question

I have been working on this for school but I am stumped. It runs but it says that it can't convert the readline to int32. I believe I have it coded right but it keeps giving me the error after I choice anything. Here is the code if someone could please tell what I did wrong. using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace ControlStructure { class ControlStructure { static int[] largeArray; // Declared array for largest number. static int[] lowArray; // Declared array for lowest number. static void Main(string[] args) { char choice; // Declares choice variable. int laCounter; // Declares lacounter variable. int counter; // Declares counter variable. int numbers; // Declares numbers variable. int input; // Declares input variable. largeArray = new int[500]; // I just intialized the array to 500 for this. lowArray = new int[500]; // Same as Above. Console.Write( "Welcome to this weeks assignment" ); // Displays Welcome message. Console.WriteLine(); // Skip a line. Console.WriteLine( "Please choose from the following choices" ); // Prompts user to decide. Console.WriteLine( "A - Find the largest # with a known quantity of numbers" ); // Displays choice A. Console.WriteLine( "B - Find the smallest # with an unknown quantity of numbers" ); // Displays choice B. Console.WriteLine( "C - Quit" ); // Displays choice C. choice = Convert.ToChar( Console.Read() ); // Reads user input and stores in choice. while ( choice != 'C' ) // Checks for the quit command. { switch ( choice ) // Switch statement to determine which choice was made. { case 'a': case 'A': { Console.Write( "Please enter the amount of numbers " ); Console.WriteLine( "you wish to process : " ); // Prompts the user for amount of numbers. laCounter = 0; laCounter = Convert.ToInt32(Console.ReadLine()); // Converts line to int and stores in laCounter. Console.WriteLine(); // Skip a line. Console.WriteLine( "You may enter the numbers now." ); // Prompts user to enter numbers. numbers = Convert.ToInt32(Console.ReadLine()); // Converts line to int and stores in numbers. for (int i = 0; i <= laCounter; i++) // For loop to navigate array. { largeArray[i] = (numbers); // Stores numbers in largeArray. } // End for statement. // Method call. Console.WriteLine( "The largest number is {0}", GetMaximum() ); break; } // End Case. case 'b': case 'B': { Console.Write ( "Please enter -999 when you have " ); Console.WriteLine ( "finished inputting numbers." ); // Informing the user to use the sentinal to stop. Console.WriteLine(); // Skip a line. Console.WriteLine( "Please enter your first number : " ); // Prompt user for number. input = Convert.ToInt32(Console.ReadLine()); while ( input != -999) // Check for sentinal { for (counter = 0; counter <= 500; counter++) { input = lowArray[counter]; } // Prompting user for another number. Console.WriteLine ( "Please enter another number or -999 : " ); input = Convert.ToInt32(Console.ReadLine()); // Coverts line to int and stores in input. } // End while. // Method call. Console.WriteLine ( "The lowest number is {0}", GetMinimum() ); break; } // End Case. default: { Console.Write( "Please select either A, B, C." ); break; } } // End switch. } // End while. Console.WriteLine("Thank you using this program."); // Displays good-bye message. } // End Main. public static int GetMaximum() // Method to find largest number in an array. { int large = largeArray[0]; // Declared large to be largeArray. foreach (int larger in largeArray) // Looks through large. { if (larger > large) // Comparing large to largest. large = larger; // If large is more than largest stores it in largest. } // End foreach. return large; // Returns the biggest int entered. } // End GetMaximum. public static int GetMinimum() // Method to find lowest number in an array. { int low = lowArray[0]; // Declared low to be lowArray. foreach ( int lower in lowArray ) // Look though low for lowest int. { if ( lower < low ) // Compares low and lowest. low = lower; // If low is less than lowest stores low in lowest. } // End foreach. return low; // Returns the lowest int input. } // End GetMinimum. } // End Class ControlStucture. } // End namespace.