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Filling a character array with characters from a string

I'm trying to fill an array with characters from a string inputted via console. I've tried the code bellow but it doesnt seem to work. I get Index out Of Range exception in the for loop part, and i didn't understand why it occured. Is the for loop range incorrect? Any insight would be greatly appreciated
Console.WriteLine("Enter a string: ");
var name = Console.ReadLine();
var intoarray = new char[name.Length];
for (var i = 0; i <= intoarray.Length; i++)
{
intoarray[i] = name[i];
}
foreach (var n in intoarray)
Console.WriteLine(intoarray[n]);

using ToCharArray() strings can be converted into character arrays.
Console.WriteLine("Enter a string: ");
var name = Console.ReadLine();
var intoarray= name.ToCharArray();
foreach (var n in intoarray)
Console.WriteLine(n);
if you are using foreach, you should wait for the index to behave as if you were taking the value.
Console.WriteLine(n);

Since arrays start at 0 and you are counting inclusive of length, the last iteration will exceed the bounds.
Just update the loop conditional to be less than length rather than less than or equal to..

I like snn bm's answer, but to answer you question directly, you're exceeding the length of the input by one. It should be:
for (var i = 0; i <= intoarray.Length - 1; i++)
(Since strings are zero-indexed, the last character in the underlying array is always going to be in the position of arrayLength - 1.)

1: the iteration should be for (var i = 0; i < intoarray.Length; i++)
2: the code
foreach (var n in intoarray)
Console.WriteLine(intoarray[n]);
also throws an exception, for "n" is a character in the array while it's used as array index.
3: In addition there's a much easier way to convert string to char array
var intoarray = name.ToCharArray();
Here's the result

Here is your mistake. There are so many options to represent i < intoarray.Length.
for (var i = 0; i < intoarray.Length; i++) // original was i <= intoarray.Length in your code
{
intoarray[i] = name[i];
}

With linq:
// Select all chars
IEnumerable<char> intoarray =
from ch in name
select ch; // can use var instead of IEnumerable<char>
// Execute the query
foreach (char temp in intoarray)
Console.WriteLine(temp);

Print ASCII of a triangle shape with variable input

Struggling with the print. I know it should be two for loops to print out the repeated letters, however, having problems to indent the lines. it should be a simple console C# program to print out the shape like below with a input 3.
XXXXX
XXX
X
With input 4 it should be like
XXXXXXX
XXXXX
XXX
X
Here is my code. Two for loops get the letters correctly but the lines all lined up at the left, not center.
static void Main(string[] args)
{
string num = Console.ReadLine().Trim();
int n = Convert.ToInt32(num);
int k=1;
for(int i = n; i>=1; i--)
{
Console.WriteLine("\n");
Console.WriteLine("".PadLeft(n));
for (int j = (2*i-1); j>=1;j--)
{
Console.Write("0");
}
}
Console.Read();
}

The statement:
Console.WriteLine("".PadLeft(n));
is the right idea but it's not quite there.
In your case, n is the number of lines you wish to print and is invariant. The number of spaces you need at the start of each line should begin at zero and increase by one for each line.
In any case, printing any number of spaces followed by newline (because it's WriteLine) is not what you want, you should be using Write instead.
So the code between int n = Convert.ToInt32(num); and Console.Read(); would be better off as something like:
for (int lineNum = 0; lineNum < n; lineNum++) {
int spaceCount = lineNum;
int xCount = (n - lineNum) * 2 - 1;
Console.Write("".PadLeft(spaceCount));
Console.WriteLine("".PadLeft(xCount, 'X'));
}
You'll notice some other changes there. First, I've used more meaningful variable names, something I'm a bit of a stickler for - using i is okay in certain circumstances but I often find it's more readable to use descriptive names.
I've also used PadLeft to do the X string as well, so as to remove the need for an inner loop.

Comparing a string[index] to another string

I am in the process of learning C# and I'm building a hangman game from scratch as one of my first projects.
Everything works except for the part that replaces the dashes of the hidden word with the correctly guessed letters.
For example: ----- becomes G-EA- after you guess G, E, and A.
I have a for loop that logically seems like it'd do the job except I can't use the == operator for strings or chars.
for (int i = 0; i <= answer.Length; i++) //answer is a string "theword"
{
if (answer[i] == passMe) //passMe is "A" for example
{
hiddenWord = hiddenWord.Remove(i, 1);
hiddenWord = hiddenWord.Insert(i, passMe);
}
}
I've scoured the net trying to find a good solution. Most recommend using Regex or other commands I haven't learned yet and therefore don't fully understand how to implement.
I've tried converting both to char format in the hope that it would fix it, but no luck so far. Thanks in advance for any help.

If passMe is a string of only one char then
if (answer[i] == passMe[0])
In this way you compare the character at i-th position with the character at the first position of your user input
There is also a serious error in your code.
Your loop goes off by one, change it to
for (int i = 0; i < answer.Length; i++)
The arrays in NET start at index zero and, the max index value possible, is always one less than the length of the array.

answer[i] refers to a character and passMe is a single character string. (not a character)
Try this
for (int i = 0; i <= answer.Length; i++) //answer is a string "theword"
{
if (answer[i] == passMe[0]) //passMe is "A" for example
{
hiddenWord = hiddenWord.Remove(i, 1);
hiddenWord = hiddenWord.Insert(i, passMe);
}
}
you need to compare a character with a character.

whats wrong in this logic of finding longest common child of string

i came up with this logic to find longest common child of two strings of equal length but it runs successfuly only on simple outputs and fails others,pls guide me what i am doing wrong here.
String a, b;
int sum = 0;
int[] ar,br;
ar = new int[26];
br = new int[26];
a = Console.ReadLine();
b = Console.ReadLine();
for (int i = 0; i < a.Length; i++)
{
ar[(a[i] - 65)]++;
br[(b[i] - 65)]++;
}
for(int i =0;i<ar.Length;i++)
{
if (ar[i] <= br[i]) { sum += ar[i]; }
else sum += br[i];
}
Console.Write(sum);
Console.ReadLine();
output:
AA
BB
0 correct.
HARRRY
SALLY
2 correct
for both above input it runs but when i submit for evaluation it fails on their test cases.i cant access their testacase on which my logic fails.i wanna know where does my logic fails.

Your second loop is all wrong. It is simply finding the count of characters that occur in both the array and the count is only updated with the the no. of the common characters contained in the string containing the least no. of these common characters.
refer this link for the correct implementation.
http://en.wikibooks.org/wiki/Algorithm_Implementation/Strings/Longest_common_substring#Retrieve_the_Longest_Substring
Also convert your input to uppercase characters using String.ToUpper before you use the input string.

C# Char permutation with repetition on large set of chars

Hello Im trying to get all possible combinations with repetitions of given char array.
Char array consists of alphabet letters(only lower) and I need to generate strings with length of 30 or more chars.
I tried with method of many for-loops,but when I try to get all combinations of char in char array with length of string more then 5 I get out of Memory Exception.
So I created similar Method that takes only first 200000 strings,then next 2000000 and so on this was proven sucessfull but only with smaller length strings.
This was my method with length of 7 chars:
public static int Progress = 0;
public static ArrayList CreateRngUrl7()
{
ArrayList AllCombos = new ArrayList();
int passed = 0;
int Too = Progress + 200000;
char[] alpha = "ABCDEFGHIJKLMNOPQRSTUVWXYZ".ToLower().ToCharArray();
for (int i = 0; i < alpha.Length; i++)
for (int i1 = 0; i1 < alpha.Length; i1++)
for (int i2 = 0; i2 < alpha.Length; i2++)
for (int i3 = 0; i3 < alpha.Length; i3++)
for (int i4 = 0; i4 < alpha.Length; i4++)
for (int i5 = 0; i5 < alpha.Length; i5++)
for (int i6 = 0; i6 < alpha.Length; i6++)
{
if (passed > (Too - 200000) && passed < Too)
{
string word = new string(new char[] { alpha[i], alpha[i1], alpha[i2], alpha[i3], alpha[i4], alpha[i5],alpha[i6] });
AllCombos.Add(word);
}
passed++;
}
if (Too >= passed)
{
MessageBox.Show("All combinations of RNG7 were returned");
}
Progress = Too;
return AllCombos;
}
I tried adding 30 for-loops with in way described above so i Would get strings with lenghts of 30 but application just hangs.Is there any better way to do this? All answers would be much appreciated. Thank you in advance!
Can someone please just post method how it is done with larger legth strings I just want to see an example? I don't have to store that data,I just need to compare it with something and release it from memory. I used alphabet for example I don't need whole alphabet.Question was not how long it would take or how much combinations would it be!!!!!

You get an OutOfMemoryException because inside the loop you allocate a string and store it in an ArrayList. The strings have to stay in memory until the ArrayList is garbage collected and your loop creates more strings than you will be able to store.
If you simply want to check the string for a condition you should put the check inside the loop:
for ( ... some crazy loop ...) {
var word = ... create word ...
if (!WordPassesTest(word)) {
Console.WriteLine(word + " failed test.");
return false;
}
}
return true;
Then you only need storage for a single word. Of course, if the loop is crazy enough, it will not terminate before the end of the universe as we know it.
If you need to execute many nested but similar loops you can use recursion to simplify the code. Here is an example that is not incredible efficient, but at least it is simple:
Char[] chars = "ABCD".ToCharArray();
IEnumerable<String> GenerateStrings(Int32 length) {
if (length == 0) {
yield return String.Empty;
yield break;
}
var strings = chars.SelectMany(c => GenerateStrings(length - 1), (c, s) => c + s);
foreach (var str in strings)
yield return str;
}
Calling GenerateStrings(3) will generate all strings of length 3 using lazy evaluation (so no additional storage is required for the strings).
Building on top of an IEnumerable generating your strings you can create primites to buffer and process buffers of strings. An easy solution is to using Reactive Extensions for .NET. Here you already have a Buffer primitive:
GenerateStrings(3)
.ToObservable()
.Buffer(10)
.Subscribe(list => ... ship the list to another computer and process it ...);
The lambda in Subscribe will be called with a List<String> with at most 10 strings (the parameter provided in the call to Buffer).
Unless you have an infinte number of computers you will still have to pull the computers from a pool and only recycle them back to the pool when they have finished the computation.
It should be obvious from the comments on this question that you will not be able to process 26^30 strings even if you have multiple computers at your disposal.

I don't have time right now to write some code but essentially if you are running out of RAM use disk. I'm thinking along the lines of one thread running an algorithm to find the combinations and another persisting the results to disk and releasing the RAM.