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C# Programming task

Hello i've got a easy programming task in C# but im stuck on the last part. I need to make 2 arrays that have random numbers (3x3) and on the end i need to sum them up in one number.
So its: array1 with 3 numbers + array2 with 3 numbers = array3 with all the array numbers addition. Can somebody please help me?
My code is:
static void Main(string[] args)
{
int[,] pole1 = new int[3, 3];
int[,] pole2 = new int[3, 3];
int[,] pole3 = new int[3, 3];
Random random1 = new Random();
Console.WriteLine("Pole 1 je: ");
for (int a = 0; a <= 2; a++)
{
for (int b = 0; b <= 2; b++)
{
pole1[a, b] = random1.Next(1, 9);
Console.Write(pole1[a, b]);
}
Console.WriteLine();
}
Console.WriteLine("Pole 2 je: ");
for (int a = 0; a <= 2; a++)
{
for (int b = 0; b <= 2; b++)
{
pole2[a, b] = random1.Next(1, 9);
Console.Write(pole2[a, b]);
}
Console.WriteLine();
}
Console.WriteLine("Součet polí je: ");
for (int a = 0; a <= 2; a++)
{
for (int b = 0; b <= 2; b++)
{
pole3[a, b] = (pole1[a, b] + pole2[a, b]);
Console.Write(pole3[a, b]);
}
Console.WriteLine();
}
Console.ReadKey();
}
}
I've got the two arrays but idk how to sum them up.

I think your code is working properly
Console.Write(pole1[a, b] + "\t"); // Add "\t"
Console.Write(pole2[a, b] + "\t"); // Add "\t"
Console.Write(pole3[a, b] + "\t"); // Add "\t"
UPDATE : if you want like bellow
Array 1 : 373
Array 2 : 176
Result : 549
Last loop will be
for (int a = 0; a <= 2; a++)
{
int sum = (pole1[a, 0] + pole2[a, 0]) * 100 + (pole1[a, 1] + pole2[a, 1]) * 10 + (pole1[a, 2] + pole2[a, 2]) ;
pole3[a, 0] = sum / 100;
pole3[a, 1] = (sum - pole3[a, 0] * 100) / 10;
pole3[a, 2] = sum - (pole3[a, 0] * 100) - (pole3[a, 1] * 10);
Console.Write($"{pole3[a, 0]}" + "\t" + $"{pole3[a, 1]}" + "\t" + $"{pole3[a, 2]}");
Console.WriteLine();
}

The Sum() method in Linq is a good goto if you want to sum up an array, however multi-dimensional arrays do not implement IEnumerable<T> by default, which can cause a few bumps in the road. Luckily Linq provides us a way to specify the type using the Cast<T> method like so:
int total = pole1.Cast<int>().Sum() + pole2.Cast<int>().Sum();
Note that I've replaced <T> with <int> as we are using generics (read more on MSDN).

Displaying an arrays index number

I need help with C#
I'm currently trying to find the minimum value in a 2D array. I have managed to do this however, after I have found the minimum value I want the corresponding values index number (Where it is stored in my 2D array) to be output. For example, I have a 2D and a 1D array. Once the minimum value has been discovered the index value for the 2D array needs to be changed in the 1D array.
The 2d array is c[i,j]
and the 1D array is a[i]
so how would i be able to display the j number in my c array in my a array. For example, if my minimum value was at c[1,5] I want the value in a[5] to be changed from 0 to 1. Any help would be great thanks!
P.S. if ive made this sound really confusing I apologise I'm new to this !
int n = 5, m = 10, MinValue = 100, MaxValue = 1, Total = 0, Sum = 0; //n = number of values m = max value in array MinValue = Lowest number in array
Random Rand = new Random();
int[] A = new int[n + 1];
for (int i = 1; i < n+1; i++) //Reached and unreached array - creation
{
A[i] = 0;
}
A[1] = 1;
int[,] c = new int[n + 1, n + 1]; //Create array
for (int i = 1; i <= n; i++)
{
for (int j = 1; j <= n; j++)
{
c[i, j] = Rand.Next(1, m); //Randomise the array
if (i == j)
{
c[i, j] = 99; // give void spaces the value of 99
}
if (c[i, j] > MaxValue && c[i, j] < 99)
{
MaxValue = c[i, j]; // max value takes the highest value (that isnt 99)
}
}
}
for (int p = 1; p <= n; p++)
{
for (int i = 1; i <= n+1; i++)
{
for (int j = 1; i <= n+1; i++)
{
if (c[i, j] <= MinValue)
{
if (A[i] == 1)
{
if (A[i] == 0)
{
Total = Sum + MinValue;
Sum = Total;
A[i] = 1;
}
}
}
}
}
}
Console.WriteLine("Total Value = " + Total);
Console.WriteLine("");
Console.WriteLine("The tracking array - what has been reached and what hasn't"); // Output reaching array
Console.WriteLine("");
for (int i = 1; i <= n; i++)
{
Console.WriteLine("A[" + i + "] = " + A[i].ToString("00") + " ");
//Output the array to screen
}
Console.WriteLine("");
Console.WriteLine("The link length array"); // Output link length array
Console.WriteLine("");
for (int i = 1; i <= n; i++)
{
for (int j = 1; j <= n; j++)
{
Console.Write("c[" + i + "," + j + "] = " + c[i, j].ToString("00") + " ");
}
Console.WriteLine();
//Output the array to screen
}
Console.WriteLine("");
Console.ReadLine();

how to calculate totals and minimum spanning trees using arrays

I'm working on a C# assignment in which i have to create a minimum spanning tree through the use of arrays. My code is made up of three arrays which track the nodes and whether or not they have been reached. I have to find the smallest total for all of the randomly generated links to be added up to visit all of the nodes. However, for some reason it is not quite working. The totals being produced are not correct and just wondered if anyone could help me work out why.I believe the error must be between the calculating of the total or how the minimum value is being decided or possible both however i am unsure.
So far i have tried changing the way it is calculated to involve a sum variable to store the values seperately. Ive attempted to add another if statement that would stop the min value from being anything above 98 ( the void value is 99) i have also tried to alter the earlier code to see if how i am testing the values in the SP array are the desired ones. still no results
int n = 5; //n = number of values
int m = 50; //m = max value in arra
int VoidValue = 99; // if i = j value = void value
int Total = 0; //Total value for spanning tree
int sum = 0; //Sum for total value for spanning tree
Random Rand = new Random(); //Create randomise value
int[,] c = new int[n + 1, n + 1]; //Cost array
int[] SP = new int[n + 1]; //Spanned array
int[,] AD = new int[n + 1, n + 1]; //Adjacency array
for (int i = 1; i <= n; i++)
{
SP[i] = 0;
for (int j = 1; j <= n; j++)
{
if (i == j)
{
c[i, j] = VoidValue; // give void spaces the value of 99
AD[i, j] = 0;
}
else
{
c[i, j] = Rand.Next(1, m); // Populate the array with randomised values
AD[i, j] = 0;
}
}
}
//Output all arrays to screen
Console.WriteLine("Cost Array: At the beginning");
Console.WriteLine("");
for (int i = 1; i <= n; i++)
{
for (int j = 1; j <= n; j++)
{
if (i == j)
{
Console.Write("c[" + i + "," + j + "] = " + "- " + " ");
}
else
{
Console.Write("c[" + i + "," + j + "] = " + c[i, j].ToString("00") + " ");
}
}
Console.WriteLine();
}
Console.ReadLine();
Console.WriteLine("");
Console.WriteLine("Spanned Array : At the beginning");
Console.WriteLine("");
for (int i = 1; i <= n; i++)
{
Console.Write("S[" + i + "] = " + SP[i].ToString("00") + " ");
Console.WriteLine();
}
Console.ReadLine();
Console.WriteLine("");
Console.WriteLine("Adjacency Array : At the beginning");
Console.WriteLine("");
for (int i = 1; i <= n; i++)
{
for (int j = 1; j <= n; j++)
{
if (i == j)
{
Console.Write("A[" + i + "," + j + "] = " + "- " + " ");
}
else
{
Console.Write("A[" + i + "," + j + "] = " + AD[i, j].ToString("00") + " ");
}
}
Console.WriteLine();
}
Console.ReadLine();
// Random Starting Point
int startPoint = Rand.Next(1, n + 1);
Console.WriteLine("Start at node " + startPoint);
SP[startPoint] = 1;
//Check the spanned array
Console.WriteLine("");
Console.WriteLine("Spanned Array : After the starting point has been chosen ");
Console.WriteLine("");
for (int i = 1; i <= n; i++)
{
Console.Write("S[" + i + "] = " + SP[i].ToString("00") + " ");
Console.WriteLine();
}
Console.ReadLine();
// Find minimum vallue link, repeatedly follow these links until spanned array is full
for (int p = 1; p < n; p++) // For every value of the spanned array
{
int MinValue = VoidValue, MinValuei = 0, MinValuej = 0; // declare variables
for (int i = 1; i <= n; i++)
{
for (int j = 1; j <= n; j++) // I and J are for both variables of the cost and adjacent array
if (i != j)
{
if (SP[i] == 1) //Spanned node
{
if (SP[j] == 0) //Unspanned node
{
if (c[i, j] < MinValue)
{
MinValue = c[i, j];
MinValuei = i;
MinValuej = j;
}
}
}
}
AD[MinValuei, MinValuej] = 1;
SP[MinValuej] = 1;
}
Console.WriteLine("");
Console.WriteLine("The min value is: " + MinValue);
Total = Total + MinValue;
Console.WriteLine("");
Console.WriteLine("The total is: " + Total);
}
//Finally output spanned and adjacent arrays
Console.WriteLine("");
Console.WriteLine("Spanned Array: After spanning tree");
Console.WriteLine("");
for (int i = 1; i <= n; i++)
{
Console.Write("S[" + i + "] = " + SP[i].ToString("00") + " ");
Console.WriteLine();
}
Console.ReadLine();
Console.WriteLine("");
Console.WriteLine("Adjacency Array : After spanning tree");
Console.WriteLine("");
for (int i = 1; i <= n; i++)
{
for (int j = 1; j <= n; j++)
{
if (i == j)
{
Console.Write("A[" + i + "," + j + "] = " + "- " + " ");
}
else
{
Console.Write("A[" + i + "," + j + "] = " + AD[i, j].ToString("00") + " ");
}
}
Console.WriteLine();
}
Console.ReadLine();
//Output total value for the spanning tree
Console.WriteLine("");
Console.WriteLine("The total value for the spanning tree: " + Total);
Console.WriteLine("");
Console.ReadLine();

My code won't do the sum; only the elements of the matrix appear and then nothing happens

namespace Suma_diagonala_secundara
{
class Program
{
static void Main(string[] args)
{
int n, i, j, s = 0;
Console.Write("n= ");
n = Convert.ToInt32(Console.ReadLine());
int[,] tab = new int[n, n];
for(i=0;i<n;i++)
for (j = 0; j < n; j++)
{
Console.Write("tab[{0}][{1}]= ", i + 1, j + 1);
tab[i, j] = Convert.ToInt32(Console.ReadLine());
}
Console.Write("\nElementele matricii sunt: ");
for (i = 0; i < n; i++)
{
for (j = 0; j < n; j++)
Console.Write("{0} ", tab[i, j]);
Console.WriteLine("");
}
Console.WriteLine("Suma elementelor de pe diagonala secundara este: ");
for (i = 0; i < n; i++)
{
s = s + tab[i, n - i + 1];
}
Console.ReadKey();
}
}
}

In your loop
for (i = 0; i < n; i++)
{
s = s + tab[i, n - i + 1];
}
you are accessing the array out of bounds, since n - 0 + 1 = n + 1 is larger than n - 1 (the largest index in tab).
What you actually want is (note the parentheses)
for (i = 0; i < n; i++)
{
s = s + tab[i, n - (i + 1)];
}

The following line:
s = s + tab[i, n - i + 1];
Is throwing an IndexOutOfRangeException because you are requesting an index higher than the array capacity.
The correct loop code is (with decrement instead increment)
for (i = 0; i < n; i++)
{
s = s + tab[i, n - i - 1];
}

how to write the value to each matrix index

For example, I have set up a formula to find my Xnew[k+1], Ynew[k+1] and Anew[k+1].
How do I pass the value to a 3 by 1 matrix if I want my
index 1,1 be Xnew[k+1],
index 1,2 be Ynew[k+1],
index 1,3 be Anew[k+1].
Here's what I got so far.
for (k = 0; k < 5; k++)
{
Xnew[k+1] = cX + (T * MPCV[k]) * Math.Cos(cA);
Ynew[k+1] = cY + (T * MPCV[k]) * Math.Sin(cA);
Anew[k+1] = cA + (T * MPCW[k]);
double[,] qK = new double[3, 1];
int i, j;
for (i = 0; i < 3; i++)
{
for (j = 0; j < 1; j++)
{
qK[i, j] = 1;
}
}
}
Thank you for the help.

Suposing Xnew[k+1], Ynew[k+1] and Anew[k+1] are doubles:
for ( k = 0; k < 5; k++ ) {
Xnew[k + 1] = cX + (T * MPCV[k]) * Math.Cos(cA);
Ynew[k + 1] = cY + (T * MPCV[k]) * Math.Sin(cA);
Anew[k + 1] = cA + (T * MPCW[k]);
double[,] qk = { { Xnew[k + 1] , Ynew[k + 1] , Anew[k + 1] } };
}
This will make you a 1x3 matrix (arrays start in 0) with:
qk[0,0] = Xnew[k+1]
qk[0,1] = Ynew[k+1]
qk[0,2] = Anew[k+1]
But if you want a 3x1 matrix use instead.
double[,] qk = { { Xnew[k + 1] }, {Ynew[k + 1] }, {Anew[k + 1] } };
That will give you:
qk[0,0] = Xnew[k+1]
qk[1,0] = Ynew[k+1]
qk[2,0] = Anew[k+1]