Question

C#, I am getting error placing them all in one file pls set them in the order that all 3 work in one file. Thanks

//Program 1

using System;
class MatrixLibrary
{
public static int[,] Matrix_Multi(int[,] a, int [,]b){
int r1= a.GetLength(0);
int c1 = a.GetLength(1);
int c2 = b.GetLength(1);
int r2 = b.GetLength(0);
if(r2 != c2){
Console.WriteLine("Matrices cannot be multiplied together.\n");
return null;
  
}else {
int[,] c = new int[r1, c2];
for (int i = 0; i < r1; i++)
{
for (int j = 0; j < c2; j++)
{
c[i, j] = 0;
for (int k = 0; k < c1; k++)
{
c[i, j] += a[i, k] * b[k, j];
}
}
}
return c;
  
}
}
public static string MatrixToString(int[,] a){
string str = "";
int p= a.GetLength(0);
int q = a.GetLength(1);
for (int i = 0; i < p; i++) {
for (int j = 0; j < q; j++) {
str = str + string.Format("{0,-4}",a[i,j]);
}
str = str + "\n";
}
return str;
}
static void Main()
{
int[,] a = {{1, 4, 2}, {2, 5, 1}};
int[,] b = {{3, 4, 2}, {3, 5, 7}, {1, 2, 1}};
Console.Write(MatrixToString(Matrix_Multi(a,b)));
  
Console.WriteLine();
int[,] P = {{10, 5, 20}, {20, 1, 7}, {10, 15, 12}};
int[,] Q = {{31, 24, 32}, {6, 2, 9}, {10, 22, 11}};
Console.Write(MatrixToString(Matrix_Multi(P,Q)));
  
Console.WriteLine();
int[,] m = {{3, 4, 2}, {3, 5, 7}, {1, 2, 1}};
int[,] n = {{1, 4, 2}, {2, 5, 1}};
Matrix_Multi(m,n);
}
}

//Program 2

using System;

namespace Delegates
{
public delegate int MyMathFunction(int x,int y);
class Program
{
static void Main(string[] args)
{
MyMathFunction myMathFunction = new MyMathFunction( Subtract);
int result = myMathFunction(7, 4);
MyMathFunction myMathFunction2 = new MyMathFunction(Multiply);
int result2 = myMathFunction2(5, 4);
MyMathFunction myMathFunction3 = new MyMathFunction(Divide);
int result3 = myMathFunction3(4, 2);
MyMathFunction myMathFunction4 = new MyMathFunction(Add);
int result4 = myMathFunction4(7, 4);
Console.WriteLine(result);
Console.WriteLine(result2);
Console.WriteLine(result3);
Console.WriteLine(result4);

}
  

public static int Add(int x, int y)
{
return (x + y);
}
public static int Multiply(int x, int y)
{
return (x * y);
}
public static int Divide(int x, int y)
{
int div = 0;
try
{
div = x / y;
}
catch (DivideByZeroException d)
{
Console.WriteLine("Cannot divide by zero");
return -1;
}
return div;
}
public static int Subtract(int x, int y)
{
return (x - y);
}

}

}

//Program 3

using System;

namespace MyPrime

{

    public class Solution

    {

        public static bool isPrime(int n, int i)

        {

            if( n < 2 )

                return false;

            else if( n == 2 )

               return true;

            else if( i >= n )

                return true;

            else if( n % i == 0 )

                return false;

            else

                return isPrime(n, i + 1);

        }

           

        public static void Main(string[] args)

        {

            Console.WriteLine("Enter n : ");

           

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

           

            if( isPrime(n, 2) == true )

                Console.WriteLine(n + " is a Prime Number");

            else

                Console.WriteLine(n + " is not a Prime Number");

        }

    }

}

Answer 1

Please find the complete code in one file from the link below:

https://www.dropbox.com/s/0kbss1kdihj7eza/ConsoleApplication1.zip?dl=0