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char 2D array compression

There is a .txt file what I have to read, compress and make an output txt for the compressed txt. Could anyone tell me what should I fix in my code?
My code:
namespace Tomorites
{
class Compression
{
public void Compress(char[,] source)
{
for (int i = 0; i < source.GetLength(0); i++)
{
int white = 0;
int red = 0;
for (int j = 0; j < source.GetLength(1); j++)
{
if (source[i, j] == 'P')
{
if (source[i, j] > 0)
{
red++;
Console.Write(red + " P ");
}
}
else if(source[i,j]=='F')
{
if (source[i, j] > 0)
{
white++;
Console.Write(white + " F ");
}
}
}
Console.WriteLine();
}
}
}
}
My console output
Source txt file
The compressed txt file which has to be

You was pretty close, but messed one important thing: reset first char counter when second char appear or second char counter when first char appear.
Also source[i, j] > 0 condition do nothing for you.
So at result we may have:
Fill source array:
static void Main(string[] args)
{
// Declare array
char[,] source = new char[7, 10];
// Fill array as at example
for (int i = 0; i < source.GetLength(0); i++)
for (int j = 0; j < source.GetLength(1); j++)
source[i, j] = i == 3 || j == 3 ? 'F' : 'P';
// Print filled array to Console
Console.WriteLine("Source:\n" + new string('-', 10));
for (int i = 0; i < source.GetLength(0); i++)
{
for (int j = 0; j < source.GetLength(1); j++)
Console.Write(source[i, j] + " ");
Console.WriteLine();
}
// Just new line
Console.WriteLine();
// Now "compress"
Console.WriteLine("Compressed:\n" + new string('-', 10));
Compress(source);
Console.ReadKey();
}
Source output:
Compress source array:
static void Compress(char[,] source)
{
// Declare counters for P and F chars
int PCount = 0, FCount = 0;
for (int i = 0; i < source.GetLength(0); i++)
{
for (int j = 0; j < source.GetLength(1); j++)
{
if (source[i, j] == 'P')
{
// If char is P - then count P's up
PCount++;
// If there was F char counted before (> 0) - print it and reset counter
if (FCount > 0)
{
Console.Write(FCount + " F ");
FCount = 0;
}
}
else if (source[i, j] == 'F')
{
// If char is P - then count F's up
FCount++;
// If there was P char counted before (> 0) - print it and reset counter
if (PCount > 0)
{
Console.Write(PCount + " P ");
PCount = 0;
}
}
}
// Before go to next "row" - print remained P or F counts and again, reset counters
if (PCount > 0)
{
Console.Write(PCount + " P ");
PCount = 0;
}
else if (FCount > 0)
{
Console.Write(FCount + " F ");
FCount = 0;
}
// Go new "row"
Console.WriteLine();
}
}
Compressed output:
UPD.
My answer is just solution for a provided example source and example output. #Dmitry Bychenko's solution is universal, not dependent on any two specific characters so in general use I recommend his way.

You can try something like this (you can fiddle with the code):
public static string Compress(char[,] source) {
if (null == source || source.GetLength(0) <= 0 || source.GetLength(1) <= 0)
return "";
StringBuilder sb = new StringBuilder();
for (int row = 0; row < source.GetLength(0); ++row) {
if (sb.Length > 0)
sb.AppendLine();
int count = 0;
char prior = '\0';
bool left = true;
for (int col = 0; col < source.GetLength(1); ++col) {
if (count == 0 || prior == source[row, col])
count += 1;
else {
if (!left)
sb.Append(' ');
left = false;
sb.Append($"{count} {prior}");
count = 1;
}
prior = source[row, col];
}
if (!left)
sb.Append(' ');
sb.Append($"{count} {prior}");
}
return sb.ToString();
}
Demo:
char[,] test = new char[,] {
{'a', 'a', 'a', 'a'},
{'a', 'b', 'c', 'c'},
};
Console.WriteLine(Compress(test));
Outcome:
4 a
1 a 1 b 2 c

How to use two dimensional array

So I have following example:
I have those 3 strings:
string seq3 = "Zeile1: 5,4,2; Zeile2: 9,4,8; Zeile3: 5,3,6";
string seq4 = "Zeile1: 2,5,4,2; Zeile2: 4,1,7,8; Zeile3: 5,3,6,1; Zeile4: 9,2,3,5";
string seq5 = "Zeile1: 2,7,5,4,2; Zeile2: 9,4,1,7,8; Zeile3: 5,3,6,7,1; Zeile4: 9,2,3,5,0; Zeile5: 7,2,5,1,6";
So I need to split the string to become 5 4 2, etc. or 2 5 4 2
And I should output it like matrix.
E.g.:
5 4 2
9 4 8
5 3 6
At the end I need calculate the arithmetic mid value. a + b / 2
So here is my method for spliting, but the dimensions don't work. I Think the method signature is wrong, I should use two dim array.
private static string[,] myArray = new string[5, 5];
public string Berechnen(string s)
{
string result ="";
string[] ZeilenInhalt = s.Split(';');
for (int i = 0; i < 5; i++)
{
string[] daten = ZeilenInhalt[i].Split(':');
string[] ascciizahlen = daten[1].Split(',');
for (int j = 0; j < 5; j++)
{
result = myArray[i, j] = ascciizahlen[j];
}
}
return result;
}
Here is the method for the output
public void Show()
{
for (int i = 0; i < myArray.GetLength(0); i++)
{
for (int j = 0; j < myArray.GetLength(1); j++)
{
Console.Write($"{myArray[i, j]}");
int middle = Convert.ToInt32(myArray[i, j]);
Console.WriteLine($"{middle,1}");
}
}
}
I used interpolate string so I can round it to comma.
The output should be smth like this:
5 4 2
9 4 8
5 3 6
Middle value: 123,2
I have only black screen.
Thanks,

If I understood you correctly, perhaps you could do something like this?
string seq3 = "Zeile1: 5,4,2; Zeile2: 9,4,8; Zeile3: 5,3,6";
string seq4 = "Zeile1: 2,5,4,2; Zeile2: 4,1,7,8; Zeile3: 5,3,6,1; Zeile4: 9,2,3,5";
string seq5 = "Zeile1: 2,7,5,4,2; Zeile2: 9,4,1,7,8; Zeile3: 5,3,6,7,1; Zeile4: 9,2,3,5,0; Zeile5: 7,2,5,1,6";
var resultArray = seq5.Split(';').Select(s => s.Split(':')[1].Trim().Split(',').Select(n => int.Parse(n)).ToArray()).ToArray();
foreach (var subArray in resultArray)
{
foreach (var number in subArray)
{
Console.Write(number);
}
Console.WriteLine($" (line average: {subArray.Average()})");
}
Console.ReadKey();
Is the mid value of each subArray lines that you need ?

Try this method for splitting:
public string[] GetMatrixFromString(string seq)
{
seq = seq.Replace("Zeile", "");
var array = seq.Split(';');
if(array.Length > 0)
{
string[] matrix = new string[array.Length];
for (int i = 0; i < array.Length; i++)
{
var item = array[i];
var matrixLine = item.Split(':')[1].Replace(",", " ");
matrix[i] = matrixLine;
}
return matrix;
}
else
{
return null;
}
}
Be careful to check if return value is null, so that in this case it was not able to parse the string and create matrix.
For example:
string seq3 = "Zeile1: 2,5,4,2; Zeile2: 4,1,7,8; Zeile3: 5,3,6,1; Zeile4: 9,2,3,5";
var matrix = GetMatrixFromString(seq3);
if(matrix == null)
{
Console.WriteLine("Unable to parse input");
}
else
{
foreach (var line in matrix)
{
Console.WriteLine(line);
}
}

Convert string from text file to integer array

I wrote this code in order to open a text file in a C# language
Each line in the file contains five digits such as
0 0 2 3 6
0 1 4 4 7
0 2 6 9 9
1 0 8 11 9
1 1 12 15 11
2 2 12 17 15
The distance between the number and the other is one tab
The problem is when you execute the program this error appears
input string was not in correct format in Convert.ToInt32(t[j])
code:
string[] st = File.ReadAllLines("C:\\testing\\result.txt");
int[,] tmp = new int[st.Length - 1, 5];
for (int i = 1; i < st.Length; i++)
{
string[] t = st[i].Split(new char[] { ' ' });
int cnt = 0;
for (int k = 0; k < t.Length; k++)
if (t[k] != "")
{ t[cnt] = t[k]; cnt++; }
for (int j = 0; j < 5; j++)
tmp[i - 1, j] = Convert.ToInt32(t[j]);
}
How can i correct that?

I suggest changing the collection type from 2d array int[,] into jagged one int[][] and then use Linq:
using System.Linq;
...
int[][] data = File
.ReadLines(#"C:\testing\result.txt")
.Select(line => line
// Uncomment this if you have empty lines to filter out:
// .Where(line => !string.IsNullOrWhiteSpace(line))
.Split(new char[] {'\t'}, StringSplitOptions.RemoveEmptyEntries)
.Select(item => int.Parse(item))
.ToArray())
.ToArray();

split char should be a tab character '\t' instead of single space

You have five numbers per row, but not necessarily five digits. You will need a more complex solution, like this:
string[] st = File.ReadAllLines("C:\\testing\\result.txt");
int[,] tmp = new int[st.Length - 1, 5];
bool isAlreadyNumber = false;
bool isEmptyRow = true;
int rowIndex = -1;
int colIndex = -1;
for (int i = 0; i < st.Length; i++) {
isAlreadyNumber = false;
isEmptyRow = true;
foreach (char c in st[i]) {
if ((c >= '0') && (c <= '9')) {
if (isAlreadyNumber) {
tmp[rowIndex][colIndex] = tmp[rowIndex][colIndex] * 10 + (c - '0');
} else {
tmp[rowIndex][colIndex] = c - '0';
if (isEmptyRow) rowIndex++;
isEmptyRow = false;
isAlreadyNumber = true;
}
} else {
isAlreadyNumber = false;
}
}
}
Note, that the indexing was fixed. This untested code handles other separators and empty lines as well, but still assumes there will be five numbers.

sum middle number with jagged array in C#

I write some code with jagged array but when i sum middle number program not working and i cant fix it...:
public class JaggedArray
{
public static void Array()
{
int[][] arrayOfArray = ArrayOfArray();
var tong = 0;
for (var i = 1; i < arrayOfArray.Length; i++)
{
for (var j = 0; j < arrayOfArray[i].Length; j++)
{
var bienTam = arrayOfArray[i].Length;
var tamThoi = j;
if (bienTam%2==0&&tamThoi==bienTam/2)
{
tamThoi++;
tong += arrayOfArray[i][tamThoi];
}
}
}
OutPut(arrayOfArray, tong);
}
private static int[][] ArrayOfArray()
{
Random ngauNhien = new Random();
int[][] arrayOfArray = new int[13][];
for (var i = 0; i <arrayOfArray.Length; i++)
{
arrayOfArray[i] = new int[i];
for (var j = 0; j < arrayOfArray[i].Length; j++)
{
arrayOfArray[i][j] = ngauNhien.Next(0, 99); //throw exception
}
}
return arrayOfArray;
}
can someone explain reason why i wrong and how ti fix it?

The problem you are solving is the one Linq is very good for:
int[][] arrayOfArray = new int[][] {
new[] {1, 2, 3}, // 2 is the middle item
new[] {4, 5} // in case of tie, let 5 (right) be the middle item
new[] {7}, // 7
new int[] {}, // should be ignored
};
// 2 + 5 + 7 == 14
var result = arrayOfArray
.Where(line => line != null && line.Length > 0)
.Sum(line => line[line.Length / 2]);

So I've got it compiling:
public class JaggedArray
{
public static void Array()
{
int[][] arrayOfArray = ArrayOfArray();
var tong = 0;
for (var i = 1; i < arrayOfArray.Length; i++)
{
for (var j = 0; j < arrayOfArray[i].Length; j++)
{
var bienTam = arrayOfArray[i].Length;
var tamThoi = j;
if (j % 2 == 0 && j / 2 == bienTam / 2)
{
tamThoi++;
// You need to check here that tamThoi isn't
// outside the bounds of your array
if (tamThoi >= arrayOfArray[i].Length)
{
continue;
}
tong += arrayOfArray[i][tamThoi];
}
}
}
}
private static int[][] ArrayOfArray()
{
Random ngauNhien = new Random();
int[][] arrayOfArray = new int[13][];
for (var i = 0; i < 13; i++)
{
arrayOfArray[i] = new int[i];
// here you're better off using i
// instead of the arrayOfArray[i].Length - because you know the length
for (var j = 0; j < i; j++)
{
arrayOfArray[i][j] = ngauNhien.Next(0, 99);
}
}
return arrayOfArray;
}
}
You can make this far more succinct with LINQ.

Text bombardment

this is the program I'm trying to write:
Write a program that reads a text and line width from the console. The program should distribute the text so that it fits in a table with a specific line width. Each cell should contain only 1 character. It should then read a line with numbers, holding the columns that should be bombarded.
My code looks like this:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace _04.Text_Bombardment
{
class Program
{
static void Main(string[] args)
{
var sentence = Console.ReadLine();
var bombing = int.Parse(Console.ReadLine());
var selected = Console.ReadLine().Split(' ').Select(int.Parse).ToArray();
Dictionary<int, bool> bombDict = new Dictionary<int, bool>();
var newSentence = sentence + new string(' ', bombing - sentence.Length % bombing); // whole row minus words left
for (int i = 0; i < selected.Length; i++)
{
bombDict.Add(selected[i], true);
}
var rows = newSentence.Length / bombing;
var cols = bombing;
var count = 0;
var arrSent = newSentence.ToCharArray();
for (int i = 0; i < rows; i++)
{
for (int j = 0; j < cols; j++)
{
if (bombDict.ContainsKey(j) && bombDict[j] == true && arrSent[count] != ' ')
{
arrSent[count] = ' ';
try
{
if (arrSent[count + bombing] == ' ')
{
bombDict[j] = false;
}
else
{
bombDict[j] = true;
}
}
catch (IndexOutOfRangeException)
{
continue;
}
}
count++;
}
}
var finalSent = string.Join("", arrSent).TrimEnd();
Console.WriteLine(finalSent);
}
}
}
And it breaks on this sentence:
Vazov received his elementary education in hisnative town of Sopoandat Plovdiv. The son of a conservative, well-to-do merchant.
20
1 6 17 2 5 0 15
Current Output:
ov eceived i e en ry educa i n hi ative to n of opo dat Plov iv. T e s of a co serva ive well-to- o mer ha t.
Intended Output:
ov eceived i e en ry educa i n hi ative to n of opo dat Plov iv. T e s of a co serva ive well-to- o mer han .
Soo it only doesn't work on the end.
Can someone help me?
Any suggestions?
Additional notes:
For example, we read the text "Well this problem is gonna be a ride." and line width 10. We distribute the text among 4 rows with 10 columns. We read the numbers "1 3 7 9" and drop bombs on those columns in the table.
The bombs destroy the character they fall on + all the neighbouring characters below it.
Note: Empty spaces below destroyed characters stop the bombs (see column 7).
Finally, we print the bombarded text on the console: "W l th s p o lem i o na be a r de."
Note: The empty cells in the table after the text should NOT be printed.

Your solution is very difficult to understand, keep it simple give names to the variables that you can understand easily.
I modified your code, hope it helps you:
static void Main()
{
string sentence = "Well this problem is gonna be a ride.";
int numberOfColumns = int.Parse("10");
List<int> bombs = "1 3 7 9".Split(' ').Select(int.Parse).ToList();
// we need to convert to decimal, otherwise C# will ignore decimal part.
//example: 127/20 = 6.35, so we need 7 rows. if we don't convert to decimal we have 6
// the Ceiling says, always round up. so even 6.1 will be rounded to 7
int numberOfRows = (int)Math.Ceiling(sentence.Length / Convert.ToDecimal(numberOfColumns));
char[,] array = new char[numberOfRows, numberOfColumns];
int sentencePointer = 0;
for (int rowIndex = 0; rowIndex < numberOfRows; rowIndex++)
{
for (int colIndex = 0; colIndex < numberOfColumns; colIndex++)
{
// if you want to print the grid with the full text, just comment the 3 lines below,
//and keep only "array[rowIndex, colIndex] = sentence[sentencePointer];"
if (bombs.Contains(colIndex))
{
if (sentence[sentencePointer] == ' ') // bomb is deactivated
{
bombs.Remove(colIndex);
array[rowIndex, colIndex] = sentence[sentencePointer];
}
else
array[rowIndex, colIndex] = '*'; // * represents a bomb
}
else
array[rowIndex, colIndex] = sentence[sentencePointer];
sentencePointer++; // move next character
if (sentencePointer >= sentence.Length)
break; // we reach the end of the sentence.
}
}
PrintGrid(array, numberOfRows, numberOfColumns);
// just give some space to print the final sentence
Console.WriteLine("");
Console.WriteLine("");
Console.WriteLine("");
for (int rowIndex = 0; rowIndex < numberOfRows; rowIndex++)
{
for (int colIndex = 0; colIndex < numberOfColumns; colIndex++)
{
Console.Write(array[rowIndex, colIndex]);
}
}
Console.ReadKey();
}
private static void PrintGrid(char[,] array, int numberOfRows, int numberOfColumns)
{
Console.WriteLine(new string('-', numberOfColumns * 2));
for (int rowIndex = 0; rowIndex < numberOfRows; rowIndex++)
{
Console.Write("|");
for (int colIndex = 0; colIndex < numberOfColumns; colIndex++)
{
Console.Write(array[rowIndex, colIndex]);
Console.Write("|");
}
Console.WriteLine("");
}
}

Somewhat more elegant solution.
private static IEnumerable<char> Bomb(IEnumerable<char> text, IEnumerable<int> indexes, int length)
{
var indexArray = new List<int>(indexes);
var used = new object[length];
return text.Select(
(c, index) =>
{
if (c != ' ' && indexArray.Contains(index % length))
{
used[index % length] = new object();
return '\0';
}
if (c == ' ' && used[index % length] != null)
{
indexArray.Remove(index % length);
}
return c;
});
}