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C# accept number and display its incrementing value using loop statements

im new to programming and we have our first activity which is to write a program that will accept a number then display its incrementing values using an array and loop statement. I tried but my code does not meet the corret way so i hope anyone can help mwle btw this is my code...
Console.WriteLine("Please input a number: ");
int put = Convert.ToInt32(Console.ReadLine());
int[] array = new int[put];
Console.WriteLine("Incremented number: ");
for (int j = 1; j <= array.Length; j++)
{
// put = put + 1;
Console.WriteLine(j);
}
Console.ReadKey();

Unless you haven't specified all the requirements, it's not completely clear what you need to do, but I assume you're asking how to populate the array and then output numbers from the array?
The typical pattern would be something like:
Console.Write("Enter the number of times to increment: ");
int put = Convert.ToInt32(Console.ReadLine()); // Not the best way to do it, but ok
// Initialize an array with the specified number of elements
int[] array = new int[put];
Console.WriteLine("\nIncremented numbers: ");
// Since arrays are 0-based, start with 0 in our loop
for (int j = 0; j < array.Length; j++)
{
// Add 1 to the current index and assign it to the appropriate array index
array[j] = j + 1;
// Output the number from the array to the console
Console.WriteLine(array[j]);
}
Console.ReadKey();

Printing square with non repetitive character

I want to print a rectangle like this :
&#*#
#*#&
*#&#
#&#*
But problem is that i can't find the algorithm to print this.
I only know how to print a simple rectangle/square
public static void Main(string[] args)
{
Console.Out.Write("Saisir la taille : ");
int taille = int.Parse(Console.In.ReadLine());
int i;
int j;
for(i = 0; i < taille; i++){
for(j = 0; j < taille; j++){
Console.Write("*");
}
Console.WriteLine("");
}
}
Thank you !

First things first unless you need your iterators outside of your loop, just declare them in the for declaration
public static void Main(string[] args)
{
Console.Out.Write("Saisir la taille : ");
int taille = int.Parse(Console.In.ReadLine());
for(int i = 0; i < taille; i++){
for(int j = 0; j < taille; j++){
Console.Write("*");
}
Console.WriteLine("");
}
}
Second you'll need a list of the characters you want to use, given your example
char[] chars = { '&', `#`, `*`, '#' };
and we'll need a way to know which character we want to use at any given time, say an iterator we can call characterIndex for simplicity. We will increment it each iteration. If incrementing it puts it out of the range of our character array, if characterIndex == 4, we set it back to zero.
int characterIndex;
To get the scrolling effect you have, before each line we must select a characterIndex that is offset by the row
characterIndex = i % chars.Length;
Tying it all together
public static void Main(string[] args)
{
char[] chars = { '&', `#`, `*`, '#' };
int characterIndex;
Console.Out.Write("Saisir la taille : ");
int taille = int.Parse(Console.In.ReadLine());
for(int i = 0; i < taille; i++){
characterIndex = i % chars.Length;
for(int j = 0; j < taille; j++){
Console.Write(chars[characterIndex]);
characterIndex++;
if(characterIndex == chars.Length)
characterIndex = 0;
}
Console.WriteLine("");
}
}

Getting the permutations by nesting for loops will only work if you know exactly how many elements there will be. Basically you need to write a for-loop for every element after the 1st.
The proper way to deal with this is Recursion. While there are cases where Recursion and nested for-loops are interchangeable. And in cases where they are, for loops have a potential speed advantage. While normally the speed rant applies to such differences, with the sheer amount of data both Recursion and Loops might have to deal with, it often maters - so best to prefer loops where possible.
Permutations is AFAIK not a case where loops and recursion are interchangeable. Recurions seems to be mandatory. Some problem as simply inherently recursive. As the recursion version is fairly well known, I will not post any example code.
You should defiitely use Recursion. With your example code I basically asume you are:
In a learning environment
You just learned recursion
A input variant recurions can effortless solve (like a 6 or 20 size input), is the next assignment

C# Algorithm Time Complexity

I have this code and I am trying to work out the time complexity of it when n=2, n=4 and n=6. Can anyone help me? I'm confused as how I do it? Big-O Notation please.
using System;
class TimeComplexityTest
{
public static void Main( string[] args)
{
int n;
Console.WriteLine("Please enter the value of n");
n = Int32.Parse(Console.ReadLine());
Console.Write("\n");
for (int i = 1; i <= 1.5*n; i++)
Console.WriteLine(i);
for (int i = n; i >= 1; i--)
Console.WriteLine(i);
Console.Read();
}
}

You have 2 loops: one running 1.5n times, and the other running 1n times.
The time complexity for that is 2.5n, which is O(n).

Sort two dimensional string array by id using insertion sort - C#

I'm new here and sorry If my question is stupid, but I really need you help.
I need to sort that two dimensional string array by id (the first column):
string [,] a = new string [,]
{
{"2","Pena","pena"},
{"1","Kon","kon"},
{"5","Sopol","sopol"},
{"4","Pastet","pastet"},
{"7","Kuche","kuche"}
};
The problem is that I'm sorting only the number and I want after them to sort the words. That's what I did so far
static void Main(string[] args)
{
string [,] a = new string [,]
{
{"2","Pena","pena"},
{"1","Kon","kon"},
{"5","Sopol","sopol"},
{"4","Pastet","pastet"},
{"7","Kuche","kuche"}
};
int b = a.GetLength(0);
Console.WriteLine(b);
Console.WriteLine(a[0,0]);
Console.WriteLine(a[0,1]);
Console.WriteLine(a[1,0]);
InsertionSort(a, b);
Console.WriteLine();
Console.Write("Sorted Array: ");
printArray(a);
Console.WriteLine();
Console.Write("Press any key to close");
Console.ReadKey();
}
public static void InsertionSort(string[,] iNumbers, int iArraySize)
{
int i, j, index;
for (i = 1; i < iArraySize; i++)
{
for (int k = 0; k < iNumbers.GetLength(1); k++)
{
index = Convert.ToInt32(iNumbers[i, 0]);
j = i;
while ((j > 0) && (Convert.ToInt32(iNumbers[j - 1, 0]) > index))
{
iNumbers[j, k] = iNumbers[j - 1, k];
j = j - 1;
}
iNumbers[j, 0] = Convert.ToString(index);
}
}
}
static void printArray(string[,] iNumbers)
{
for (int i = 0; i < iNumbers.GetLength(0); i++)
{
for (int k = 0; k < iNumbers.GetLength(1); k++)
{
Console.Write(iNumbers[i, k] + " ");
}
}
Console.WriteLine();
}
Unfortunatelly as output I get
1 Pena pena 2 Kon kon 4 Sopol sopol 5 Pastet pastet 7 Kuche kuche
I would be really grateful if you could help me.

Based on the nature of the example and the question, I am guessing that this is a homework assignment and so must be implemented in a fashion that is a) not far from your current example, and b) actually demonstrates an insertion sort.
With that in mind, the following is a corrected version of your example that works:
public static void InsertionSort(string[,] iNumbers, int iArraySize)
{
int i, j, index;
for (i = 1; i < iArraySize; i++)
{
index = Convert.ToInt32(iNumbers[i, 0]);
j = i;
while ((j > 0) && (Convert.ToInt32(iNumbers[j - 1, 0]) > index))
{
for (int k = 0; k < iNumbers.GetLength(1); k++)
{
string temp = iNumbers[j, k];
iNumbers[j, k] = iNumbers[j - 1, k];
iNumbers[j - 1, k] = temp;
}
j = j - 1;
}
}
}
I made two key changes to your original code:
I rearranged the k and j loops so that the k loop is the inner-most loop, rather than the j loop. Your j loop is the one performing the actual sort, while the k loop is what should be actually moving a row for an insertion operation.
In your original example, you had this reversed, with the result that by the time you went to sort anything except the index element of a row, everything looked sorted to the code (because it's only comparing the index element) and so nothing else got moved.
With the above example, the insertion point is determined first, and then the k loop is used simply to do the actual insertion.
I added logic to actually swap the elements. In your original code, there wasn't really a swap there. You had hard-coded the second part of a swap, simply copying the index element to the target, so the swap did work for the index element. But it wouldn't have achieved the swap for any other element; instead, you'd just have overwritten data.
With the above, a proper, traditional swap is used: one of the values to be swapped is copied to a temp local variable, the other value to be swapped is copied to the location of the first value, and then finally the saved value is copied to the location of the second.
The above should be good enough to get you back on track with your assignment. However, I will mention that you can get rid of the k loop altogether if your teacher will allow you to implement this using jagged arrays (i.e. a single-dimensional array containing several other single-dimensional arrays), or by using a second "index array" (i.e. where you swap the indexes relative to the original array, but leave the original array untouched).

Using a nested for loop and getting unexpected repetitions in c#

I've the following code in c# visual basic 2010:
for (int i = 7; i > 0; i--)
{
Char star = '*';
string numbers = "765432" ;
//Console.WriteLine(star);
for (int a = 0; a < i; a++)
{
Console.Write(star);
}
for (int b = 0; b < i; b++)
{
numbers.TrimEnd(numbers[numbers.Length - 1]);
Console.Write(numbers);
}
Console.WriteLine();
}
Console.ReadLine();
I was expecting the outcome:
*765432
repeated on the screen 7 times, instead I get:
*****765432765432765432765432765432
****765432765432765432765432
***765432765432765432
**765432765432
*765432
(I can't display the full outcome because it doesn't come back properly on screen but it's basically the variables star and numbers displayed 7 times on line 1, 6 times on line 2 etc. until once in line 7)
My understanding is that the a and b variables declared in the for loops should dictate how many times the for loop is entered into, why are the star and numbers variables also being written 7 times then 6 times to match the number of times the loop is entered into? Especially when they are initialised as * and 765432?

This is the problem (I suspect, anyway - it's certainly a problem):
numbers.TrimEnd(numbers[numbers.Length - 1]);
Strings are immutable in .NET. TrimEnd doesn't change the existing string - it returns a reference to a new one. As highlighted in the documentation:
This method does not modify the value of the current instance. Instead, it returns a new string in which all trailing characters found in trimChars are removed from the current string.
You'd also be better off using Substring for simplicity to "remove" the last character:
numbers = numbers.Substring(0, numbers.Length - 1);
Or indeed Remove:
numbers = numbers.Remove(numbers.Length - 1);
... although this will actually fail on the 7th iteration as the string will be empty at this point. It's not really what you were trying to achieve, but I think you need to take a step back from it and think carefully about each step in the process.

TrimEnd returns a new string, it doesn't modify the original string. You have to assign it back to number. Strings are immutable.
number = numbers.TrimEnd(numbers[numbers.Length - 1]);
Check for string length before indexing its element. In your for loop you can add the condition like:
for (int b = 0; b < i && numbers.Length > 0; b++)

No. The 'a' for loop runs, outputting that many stars, and the 'b' for loop runs next, outputting that many strings. If you just want '*765432' to repeat 7 times, you need to change
for (int a = 0; a < i; a++)
{
Console.Write(star);
}
for (int b = 0; b < i; b++)
{
numbers.TrimEnd(numbers[numbers.Length - 1]);
Console.Write(numbers);
}
To
for (int a = 0; a < 7; a++)
{
Console.Write(star);
Console.Write(numbers);
}
And take out the parent loop; that's what is giving you the incrementingly shorter lines.

This produce the output you are expecting:
for (int i = 0; i < 7; i++)
{
Char star = '*';
string numbers = "765432" ;
Console.WriteLine(star);
Console.Write(numbers);
Console.WriteLine();
}
I was expecting the outcome: *765432 repeated on the screen 7 times

You never need to use TrimEnd() and multiple for loop in this situation.
public static void Main()
{
for (int i = 7; i > 0;i--)
{
char star = '*';
string numbers = "765432";
Console.WriteLine(star + numbers);
}
Console.ReadLine();
}
output:
*765432
*765432
*765432
*765432
*765432
*765432
*765432