How can I change numbers into letters in C# - c#

I have code like this:
for (int i = 1; i < max; i++)
{
<div>#i</div>
<div>#test[i]</div>
}
I'm using MVC3 razor syntax so it might look a bit strange.
My max is always less than ten and I would like to have a value like "A", "B" .. etc appear between the first instead of the number "1", "2" .. which is the value of i. Is there an easy way I can convert i to a letter where i = 1 represent "A" and i=2 represents "B". I need to do this in C# which I can place in my MVC3 view file.
Marife

Personally I'd probably use the indexer into a string:
// Wherever you want to declare this
// As many as you'll need - the "X" is to put A=1
const string Letters = "XABCDEFGHIJKLMNOP";
...
<div>
for (int i = 1; i < max; i++)
{
<div>#i</div>
<div>#Letters[i]</div>
}
I find that simpler and more flexible than bit shifting etc, although that will certainly work too.

(char)(i + 64) will work (65 = 'A')
for (int i = 1; i < max; i++)
{
char c = (char)(i + 64); // c will be in [A..J]
...
}

You could shift i by 64 (with a 1-based index) and cast your int to a char.

If you don't need to use i anywhere else you can do this:
for (Char ch = 'A'; ch < 'K'; ch++)
{
MessageBox.Show(ch.ToString());
}
Ah, just realised the last letter isn't constant, so you would need to convert a number somwwehere.

Related

PadRight in string of arrays doesn't add chars

I created array of strings which includes strings with Length from 4 to 6. I am trying to PadRight 0's to get length for every element in array to 6.
string[] array1 =
{
"aabc", "aabaaa", "Abac", "abba", "acaaaa"
};
for (var i = 0; i <= array1.Length-1; i++)
{
if (array1[i].Length < 6)
{
for (var j = array1[i].Length; j <= 6; j++)
{
array1[i] = array1[i].PadRight(6 - array1[i].Length, '0');
}
}
Console.WriteLine(array1[i]);
}
Right now the program writes down the exact same strings I have in array without adding 0's at the end. I made a little research and found some informations about that strings are immutable, but still there are some example with changing strings inside, but I couldn't find any with PadRight or PadLeft and I fell like there must be a way to do it, but I just can't figure it out.
Any ideas on how to fix that issue?
The first argument to PadRight is the total length you want. You've specified 6 - array1[i].Length - and as all your strings start off with at least 3 characters, you're padding to at most 3 characters, so it's not doing anything.
You don't need your inner loop, and your outer loop condition is more conventionally written as <. This is one way I'd write that code:
using System;
public class Test
{
static void Main()
{
string[] array =
{
"aabc", "aabaaa", "Abac", "abba", "acaaaa"
};
for (var i = 0; i < array.Length; i++)
{
array[i] = array[i].PadRight(6, '0');
Console.WriteLine(array[i]);
}
}
}
In fact I'd probably use foreach, or even Select, but that's a different matter. I've left this using an array to be a bit closer to your original code.

Selection sort with strings

Okay, I've been using this code to do a selection sort on integers:
public void selectSort(int [] arr)
{
//pos_min is short for position of min
int pos_min,temp;
for (int i=0; i < arr.Length-1; i++)
{
pos_min = i; //set pos_min to the current index of array
for (int j=i+1; j < arr.Length; j++)
{
if (arr[j] < arr[pos_min])
{
//pos_min will keep track of the index that min is in, this is needed when a swap happens
pos_min = j;
}
}
//if pos_min no longer equals i than a smaller value must have been found, so a swap must occur
if (pos_min != i)
{
temp = arr[i];
arr[i] = arr[pos_min];
arr[pos_min] = temp;
}
}
}
but now I want to run the same algorithm on a string list instead.
How could that be accomplished? It feels really awkward and like you would need additional loops to compare multiple chars of different strings..?
I tried a lot, but I couldn't come up with anything useful. :/
Note:
I know, selection sort isn't very efficient. This is for learning purposes only. I'm not looking for alternative algorithms or classes that are already part of C#. ;)
IComparable is an interface that gives us a function called CompareTo, which is a comparison operator. This operator works for all types which implement the IComparable interface, which includes both integers and strings.
// Forall types A where A is a subtype of IComparable
public void selectSort<A>(A[] arr)
where A : IComparable
{
//pos_min is short for position of min
int pos_min;
A temp;
for (int i=0; i < arr.Length-1; i++)
{
pos_min = i; //set pos_min to the current index of array
for (int j=i+1; j < arr.Length; j++)
{
// We now use 'CompareTo' instead of '<'
if (arr[j].CompareTo(arr[pos_min]) < 0)
{
//pos_min will keep track of the index that min is in, this is needed when a swap happens
pos_min = j;
}
}
//if pos_min no longer equals i than a smaller value must have been found, so a swap must occur
if (pos_min != i)
{
temp = arr[i];
arr[i] = arr[pos_min];
arr[pos_min] = temp;
}
}
}
The System.String class has a static int Compare(string, string) method that returns a negative number if the first string is smaller than the second, zero if they are equal, and a positive integer if the first is larger.
By "smaller" I mean that it comes before the other in the lexical order and by larger that it comes after the other in lexical order.
Therefore you can compare String.Compare(arr[j], arr[pos_min]) < 0 instead of just arr[j] < arr[pos_min] for integers.
I am writing the code in python 3.6
First import sys module for use of various features in our syntax.
import sys
Consider an array of string data type items.
A = ['Chuck', 'Ana', 'Charlie', 'Josh']
for i in range(0, len(A)):
min_val = i
for j in range(i+1, len(A)):
if A[min_val] > A[j]:
min_val = j
Swapping the indexed and minimum value here.
(A[min_val], A[i]) = (A[i], A[min_val])
print("Sorted Array is :")
for i in range(len(A)):
print("%s" % A[i])
This works perfectly fine for an array of string datatype and sorts out the input data in an alphabetical way out.
As in the input 'Charlie' and 'Chuck' are being compared according to their alphabetical preference till the 3rd place and arranged accordingly.
The output of this program on python console is
Sorted Array is :
Ana
Charlie
Chuck
Josh

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.

Get all possible word combinations

I have a list of n words (let's say 26). Now I want to get a list of all possible combinations, but with a maximum of k words per row (let's say 5)
So when my word list is: aaa, bbb, ..., zzz
I want to get:
aaa
bbb
...
aaabbb
aaaccc
...
aaabbbcccdddeeefff
aaabbbcccdddeeeggg
...
I want to make it variable, so that it will work with any n or k value.
There should be no word be twice and every combinations needs to be taken (even if there are very much).
How could I achieve that?
EDIT:
Thank you for your answers. It is not an assignment. Is is just that I forgot the combinations of my password and I want to be sure that I have all combinations tested. Although I have not 26 password parts, but this made it easier to explain what I want.
If there are other people with the same problem, this link could be helpfull:
Generate word combination array in c#
i wrote simple a function to do this
private string allState(int index,string[] inStr)
{
string a = inStr[index].ToString();
int l = index+1;
int k = l;
var result = string.Empty;
var t = inStr.Length;
int i = index;
while (i < t)
{
string s = a;
for (int j = l; j < k; j++)
{
s += inStr[j].ToString();
}
result += s+",";
k++;
i++;
}
index++;
if(index<inStr.Length)
result += allState(index, inStr);
return result.TrimEnd(new char[] { ',' });
}
allState(0, new string[] { "a", "b", "c"})
You could take a look at this
However, if you need to get large numbers of combinations (in the tens of millions) you should use lazy evaluation for the generation of the combinations.

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