I've written the following method in C# for a small Forms program I'm working on, but whenever I try to run this method the entire program freezes.
There are no errors and I've tried to do for (int n = 0; n<8; n++) instead of while(true), but that didn't seem to change anything...
Any ideas?
Thanks in advance!
public bool legalMove(int y, int x)
{
// Check if the cell is occupied
if (grid[x, y] != 0)
return false;
// Check if there's an opponents circle somewhere around it
for (int i = -1; i<=1; i++)
for (int j = -1; i<=1; j++)
{
if (i == 0 && j == 0)
continue;
int row = x + i;
int col = y + j;
if (row >= 0 && row < 8 && col >= 0 && col < 8 && grid[col,row] == -turn)
{
// Now we know that there's an opponents circle somewhere around this space, we now check if it can be captured
while(true)
{
row += i;
col += j;
if (row < 0 || row > 7 || col < 0 || col > 7 || grid[row, col] == 0)
return false; // Outside of the board or an empty space
else if (grid[row, col] == turn)
return true; // No empty spaces between our cell and another cell of ours
}
}
}
return false; // No cell found around ours
}
Here's the problem: for (int j = -1; i<=1; j++). Should be j<=1 instead of i<=1.
I'm coming back to programming after having done none for several years, and created a Sudoku game to get my feet wet again. I've written a recursive function to brute-force a solution, and it will do so for simple board states, but runs into a stack overflow most of the time for more complicated board states. I know that this could be averted using loops or a more efficient algorithm, but since this is for the sake of learning I want to know how to allocate more memory to the stack (acknowledging this isn't the best solution to the problem).
An answer here: How to change stack size for a .NET program? that recommends using a thread with more memory allocated isn't working, as from what I can read .NET 4.0 will not let you increase a thread's maximum allocated memory beyond the default.
Another solution recommends using EDITBIN.EXE, but I am new to Visual Studio and have not found an explanation I understand of how to do so.
Similarly, I've found that you can use a .def file to indicate a larger default stack size, but have not found an explanation I understand of how to create/implement one.
Can anyone offer newbie-level explanations of either EDITBIN.EXE or .def file implementations, or offer another way to increase the stack size?
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.IO;
namespace Sudoku
{
//object keeps track of the value of all numbers currently on the board using an array
class BoardState
{
int testcount = 1;
//3d array of ints representing all values on the board, represted as region, column, row
int[,,] boardVals;
//3d array of bools representing if a number is immutable (true cannot be changed, false can be)
bool[,,] fixedVals;
//create a blank board if no initial values are provided
public BoardState()
{
boardVals = new int[9, 3, 3];
fixedVals = new bool[9, 3, 3];
}
//create a board with the listed initial values as immutable
public BoardState(int[,,] inputVals)
{
boardVals = inputVals;
fixedVals = new bool[9,3,3];
for (int i = 0; i < 9; ++i)
for (int j = 0; j < 3; ++j)
for (int k = 0; k < 3; ++k)
if (boardVals[i, j, k] > 0) fixedVals[i, j, k] = true;
}
//update the state of the board using the coordinates of a single value
//**note** method has not been implemented and tested yet
public void updateState(int region, int column, int row, int val)
{
if (!fixedVals[region, column, row])
{
boardVals[region, column, row] = val;
}
}
//update the state of the board to match the state of another board
public void updateState(int[,,] newState)
{
boardVals = newState;
}
public int[,,] getVals()
{
return boardVals;
}
public bool[,,] getFixed()
{
return fixedVals;
}
//set all non-zero values to be immutable
public void setFixed()
{
for (int i = 0; i < 9; i++)
for (int j = 0; j < 3; j++)
for (int k = 0; k < 3; k++) {
if (boardVals[i, j, k] != 0)
fixedVals[i, j, k] = true;
else
fixedVals[i, j, k] = false;
}
}
//test method
public void testState()
{
for (int i = 0; i < 9; i++)
for (int j = 0; j < 3; j++)
for (int k = 0; k < 3; k++)
Console.WriteLine(boardVals[i, k, j]);
}
//accepts a 3d array representing the current board state.
//returns a 3d bool array denoting whether any region, row, or column is invalid (true=invalid)
//first value of array designates the region, row, or column respectively
//second value designates which of those is invalid
public bool[,] validateBoard()
{
bool[,] valid = new bool[3, 9];
int[,] rows = makeRows(boardVals);
int[,] cols = makeCols(boardVals);
//compare each value in each row to each other value in that row
for (int i = 0; i < 9; i++)
{
for (int j = 0; j < 9; j++)
{
//only validate an entry if it has been assigned a value
if (rows[i, j] != 0)
{
for (int k = 0; k < 9; k++)
{
//if two values are not the same entry and are equal, set that entry to invalid
if (j != k && rows[i, j] == rows[i, k])
valid[1, i] = true;
}
}
}
}
//compare each value in each column to each other value in that column
for (int i = 0; i < 9; i++)
{
for (int j = 0; j < 9; j++)
{
//only validate an entry if it has been assigned a value
if (cols[i, j] != 0)
{
for (int k = 0; k < 9; k++)
{
//if two values are not the same entry and are equal, set that entry to invalid
if (j != k && cols[i, j] == cols[i, k])
valid[2, i] = true;
}
}
}
}
//compare each value in each region to each other value in that region
for (int i = 0; i < 9; i++)
{
for (int j = 0; j < 3; j++)
{
for (int k = 0; k < 3; k++)
{
//only validate an entry if it has been assigned a value
if (boardVals[i, j, k] != 0)
{
for (int l = 0; l < 3; l++)
{
for (int m = 0; m < 3; m++)
{
//if two values are not the same entry and are equal, set that entry to invalid
if (!(l == j && m == k) && boardVals[i, j, k] == boardVals[i, l, m])
valid[0, i] = true;
}
}
}
}
}
}
return valid;
}
public bool isValid()
{
bool retFlag = true;
bool[,] valid = new bool[3, 9];
int[,] rows = makeRows(boardVals);
int[,] cols = makeCols(boardVals);
//for (int i = 0; i < 9; i++)
// for (int j = 0; j < 3; j++)
// for (int k = 0; k < 3; k++)
// Console.Write(boardVals[i, j, k]);
//compare each value in each row to each other value in that row
for (int i = 0; i < 9; i++)
{
for (int j = 0; j < 9; j++)
{
//only validate an entry if it has been assigned a value
if (rows[i, j] != 0)
{
for (int k = 0; k < 9; k++)
{
//if two values are not the same entry and are equal, set that entry to invalid
if (j != k && rows[i, j] == rows[i, k])
{
retFlag = false;
}
}
}
}
}
//compare each value in each column to each other value in that column
for (int i = 0; i < 9; i++)
{
for (int j = 0; j < 9; j++)
{
//only validate an entry if it has been assigned a value
if (cols[i, j] != 0)
{
for (int k = 0; k < 9; k++)
{
//if two values are not the same entry and are equal, set that entry to invalid
if (j != k && cols[i, j] == cols[i, k])
{
retFlag = false;
}
}
}
}
}
//compare each value in each region to each other value in that region
for (int i = 0; i < 9; i++)
{
for (int j = 0; j < 3; j++)
{
for (int k = 0; k < 3; k++)
{
//only validate an entry if it has been assigned a value
if (boardVals[i, j, k] != 0)
{
for (int l = 0; l < 3; l++)
{
for (int m = 0; m < 3; m++)
{
//if two values are not the same entry and are equal, set that entry to invalid
if (!(l == j && m == k) && boardVals[i, j, k] == boardVals[i, l, m])
{
retFlag = false;
}
}
}
}
}
}
}
return retFlag;
}
//returns an array of all the values in each row
public int[,] makeRows(int[,,] boardState)
{
int[,] rows = new int[9, 9];
for (int i = 0; i < 9; i++)
for (int j = 0; j < 9; j++)
rows[i, j] = boardState[j / 3 + ((i / 3) * 3), j % 3, i - ((i / 3) * 3)];
return rows;
}
//returns an array of all values in each column
public int[,] makeCols(int[,,] boardState)
{
int[,] cols = new int[9, 9];
for (int i = 0; i < 9; i++)
for (int j = 0; j < 9; j++)
cols[i, j] = boardState[((j / 3) * 3) + (i / 3), i - ((i / 3) * 3), j % 3];
return cols;
}
//update the board state to a state read in from a file
public void updateFromFile(Stream update)
{
int[,,] newVals = new int[9, 3, 3];
int[,,] newFixed = new int[9, 3, 3];
StreamReader file = new StreamReader(update);
for (int i = 0; i < 9; i++){
for (int j = 0; j < 3; j++){
for (int k = 0; k < 3; k++){
boardVals[i, j, k] = (int)char.GetNumericValue((char)file.Read());
}
}
}
for (int i = 0; i < 9; i++){
for (int j = 0; j < 3; j++){
for (int k = 0; k < 3; k++){
fixedVals[i, j, k] = (0 != ((int)char.GetNumericValue((char)file.Read())));
}
}
}
file.Close();
}
public void Solve(int entry, int val)
{
Console.WriteLine("This is call number " + ++testcount);
//returns if all values are filled and valid
if (entry == 81)
{
Console.WriteLine("Solved!");
return;
}
//creating reference coordinates based on entry value
int reg = entry / 9;
int col = (entry - (reg * 9)) % 3;
int row = (entry - (reg * 9)) / 3;
//if current entry being checked is a fixed value, go the next value
if (!fixedVals[reg, row, col])
{
Console.WriteLine("");
Console.WriteLine("Making an attempt at entry " + entry + " using value " + val);
Console.WriteLine("This entry is at region " + reg + ", col " + col + ", row " + row);
//assign entry the value to be tested
boardVals[reg, row, col] = val;
//if the value is valid, go to the next entry
if (isValid())
{
Console.WriteLine("Entry Valid at " + entry);
val = 1;
entry++;
Console.WriteLine("Trying the next entry at " + entry);
Solve(entry, val);
}
//if the value is invlid and all 9 values have not been tried,
//increment value and call again at same entry
if (!isValid() && val < 9)
{
Console.WriteLine("Entry Invalid at " + entry + " with value " + val);
++val;
Console.WriteLine("Trying again with value " + val);
Solve(entry, val);
}
//if the value in invalid and all 9 values have been tried,
//zero out the entry and go back to the previous non-fixed entry
if (!isValid() && val == 9)
{
do
{
boardVals[reg, row, col] = 0;
Console.WriteLine("Reached Value 9 and was still invalid");
--entry;
Console.WriteLine("Trying again at entry " + entry);
Console.WriteLine("The value at that entry is " + boardVals[reg, row, col]);
reg = entry / 9;
col = (entry - reg * 9) % 3;
row = (entry - reg * 9) / 3;
if (fixedVals[reg, row, col])
Console.WriteLine("But that's a fixed value, so I'll go back one more");
Console.WriteLine("");
} while (boardVals[reg, row, col] == 9 || fixedVals[reg, row, col]);
val = boardVals[reg, row, col] + 1;
Solve(entry, val);
}
}
else Solve(++entry, val);
}
}
}
The big bad warning
If you use recursion in a program and reach a point where having a StackOverflowException is an actual threat, please do not consider increasing the stack size as a valid solution.
If you encounter a StackOverflowException you are doing something very wrong; you should instead be using a Stack<T> for depth-first processing, or a Queue<T> for breadth-first processing. Example.
The solution
This can be achieved by using editbin.exe, which is installed with this package;
Find the location of editbin.exe, mine was located at C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\VC\Tools\MSVC\14.14.26428\bin\Hostx64\x64\editbin.exe, I would suggest using Everything by voidtools in lieu of Microsoft's awful search to find this.
Set the stack size manually
Navigate to your bin folder and execute the following:
"<full path of editbin.exe>" /stack:<stack size in bytes, decimal> <your executable name>
For example I executed this:
"C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\VC\Tools\MSVC\14.14.26428\bin\Hostx64\x64\EDITBIN.EXE" /stack:2097152 ExampleProgram.exe
Which set the stack reserve size to 2MB.
With this I was capable of reaching twice the recursion level; (1MB stack reserve on left, 2MB stack reserve on right).
Set the stack size automatically
Right click on your project and select 'Options', then click on 'Build Events' and add the following to your post-build events:
"<full path of editbin.exe>" /stack:<stack size in bytes, decimal> "$(TargetPath)"
For example I added
"C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\VC\Tools\MSVC\14.14.26428\bin\Hostx64\x64\EDITBIN.EXE" /stack:2097152 "$(TargetPath)"
This will run editbin.exe every time you build your executable.
Note: You will see a lot lower level of recursion reached when running your program from Visual Studio as you will from running it explicitly via explorer or cmd. You will still however see a 2x increase in the level of recursion met if moving from a 1MB stack reserve to a 2MB stack reserve.
Perhaps set the Stack Reserve Size in Visual Studio:
Project -> Properties -> Configuration Properties -> Linker -> System -> Stack Reserve Size
This can also be done via the command-line or programatically when a thread is created:
https://learn.microsoft.com/en-us/cpp/build/reference/stack-stack-allocations?view=vs-2017
How can i make this so the user types positions in console (table[4,5]) i want that user types that?
int[,] table = new int[8, 8];
for (int i = 0; i < 8; i++)
{
for (int j = 0; j < 8; j++)
{
if ((i + j) % 2 == 0)
{
table[i, j] = 0;
}
else
{
table[i, j] = 1;
}
}
}
Console.WriteLine("4 - king");
Console.WriteLine("3 - queen");
Console.WriteLine("4 - hunter");
table[4,5] = 2;
table[6,7] = 3;
table[2,2] = 4;
for (int i = 0; i < 8; i++)
{
for (int j = 0; j < 8; j++)
{
Console.Write(table[i, j] + " ");
}
Console.WriteLine();
}
What should i do to make this work?And if i type this it doesnt work:
Thats why i have to put figures in different rows or columns how do i fix this
table[4,5] = 2;
table[4,7] = 3;
table[2,2] = 4;
You are confusing the assignment operator "=" with the logical comparison operator "==". Your second line is just comparing table[4,5] with 2 and probably returning false.
Change it to:
table[4,5] = 2;
Also, even if you manage to assign a value to table[4,5], you will overwrite it in the next lines. You should move that line to the end of the first nested loop. Just before the second "for (int i = 0; i < 8; i++)"
//export header
for (i = 1; i <= this.datagridview1.Columns.Count; i++)
{
ExcelSheet.Cells[3, i] = this.datagridview1.Columns[i - 1].HeaderText;
}
//export data
for (i = 1; i <= this.datagridview1.RowCount; i++)
{
for (j = 1; j <= datagridview1.Columns.Count; j++)
{
ExcelSheet.Cells[i + 3, j] = datagridview1.Rows[i - 1].Cells[j - 1].Value;
}
}
This is exporting all data from datagridview but I don't want to export "Date " column and "checkbox" column
Showing like this
You can use an additional counter for columns to get the proper output (not just empty columns). Also, you can move the logics of "skipping" columns to a function.
int columnsCount = 0;
//export header
for (i = 1; i <= this.datagridview1.Columns.Count; i++)
{
if (SkipColumn(this.datagridview1.Columns[i - 1]))
continue;
columnsCount++;
ExcelSheet.Cells[3, columnsCount] = this.datagridview1.Columns[columnsCount - 1].HeaderText;
}
//export data
for (i = 1; i <= this.datagridview1.RowCount; i++)
{
columnsCount = 0;
for (j = 1; j <= datagridview1.Columns.Count; j++)
{
if (SkipColumn(this.datagridview1.Columns[i - 1]))
continue;
columnsCount++;
ExcelSheet.Cells[i + 3, columnsCount] = datagridview1.Rows[i - 1].Cells[columnsCount - 1].Value;
}
}
// ...
private bool SkipColumn(DataGridViewColumn column)
{
return column.GetType() == typeof(DataGridViewCheckBoxColumn)
|| column.Name == "Date";
}
You can add any logics to SkipColumn. Add any validations, conditions there using DataGridViewColumn properties.
Read about DataGridViewColumn properties at MSDN.
I'm taking a class that uses C# and our first assignment is to implement Conway's game of Life. We must do this by reading in a text file formatted something like this:
*
*
***
***
We then have to display the next 10 generations on the screen.
I have the file read into a string array, then I copy it to another array. I then go through it character by character and change the copied array to match what the next generation should be. My problem is that the code I have to count the live neighbors isn't working and I can't figure out why. I displayed the number of live neighbors for each cell on the screen and about half of them are wrong. I know the error is occurring with cells on the edge of the "board," but I can't figure out how to fix it.
Now, I don't want the whole thing written for me, that'd be a bit pointless. I just can't figure out where my logic is off. Any help would be appreciated. Also, I'm aware that my code is pretty poor, overall. This was just the only way I could figure it out. Sorry.
class Program
{
static void Main(string[] args)
{
//gets file name from command arguments
//checks to make sure file exists, exits if file does not exist
if (!File.Exists(Environment.GetCommandLineArgs()[1])) { System.Environment.Exit(1); }
//gets file name from command arguments then reads file into array of strings
string[] gen0 = File.ReadAllLines(Environment.GetCommandLineArgs()[1]);
string[] gen1 = gen0;
char alive = '*';
char dead = ' ';
//displays first generation
foreach (string s in gen0)
{
Console.WriteLine(s);
}
Console.WriteLine("=====================================");
//counts live neighbors of a cell
int count = 0;
for (int i = 0; i < gen0.Length; i++)
{
count = 0;
for (int j = 0; j < gen0[i].Length; j++)
{
//check top left neighbor
if (i > 0 && j > 0 && j < gen0[i-1].Length )
{
if (gen0[i - 1][j - 1] == alive) { count++; }
}
//check above neighbor
if (i > 0 && j < gen0[i-1].Length)
{
if (gen0[i - 1][j] == alive) { count++; }
}
//check top right neighbor
if (i > 0 && j + 1 < gen0[i - 1].Length)
{
if (gen0[i - 1][j + 1] == alive) { count++; }
}
//check left neighbor
if (j > 0)
{
if (gen0[i][j - 1] == alive) { count++; }
}
//check right neighbor
if (j + 1 < gen0[i].Length)
{
if (gen0[i][j + 1] == alive) { count++; }
}
//check bottom left neighbor
if (i + 1 < gen0.Length && j > 0 && j < gen0[i+1].Length)
{
if (gen0[i + 1][j - 1] == alive) { count++; }
}
//check below neighbor
if (i + 1 < gen0.Length && j < gen0[i+1].Length)
{
if (gen0[i + 1][j] == alive) { count++; }
}
//check bottom right neighbor
if (i + 1 < gen0.Length && j + 1 < gen0[i].Length && j + 1 < gen0[i+1].Length)
{
if (gen0[i + 1][j + 1] == alive) { count++; }
}
//Console.WriteLine(count);
//kills cells
if (count < 2 || count > 3)
{
gen1[i] = gen1[i].Remove(j, 1);
gen1[i] = gen1[i].Insert(j, dead.ToString());
}
//births cells
if (count == 3)
{
gen1[i] = gen1[i].Remove(j, 1);
gen1[i] = gen1[i].Insert(j, alive.ToString());
}
}
}
foreach (string s in gen1)
{
Console.WriteLine(s);
}
}
}
Your problem is very simple - you're resetting count in the wrong place. Put it inside the loop and it will (probably) work.
Regarding the rest of the code, if you want to make it significantly easier to follow just give your game area a one-element border.
You'll need to pad the file you read in (blank line above and below, blank characters to the left and right), and alter your loops to:
for (int i = 1; i < gen0.Length - 1; i++)
and
for (int j = 1; j < gen0[i].Length - 1; j++)
but your central count calculation can then be reduced down to a single calculation:
count = (gen0[i - 1][j - 1] == alive) ? 1 : 0 +
(gen0[i - 1][j] == alive) ? 1 : 0 +
... etc ...
which should make for cleaner code and ensure that any other errors you may make are significantly easier to spot.
So the first bug I see is that you don't actually copy the board for the next iteration.
gen1 = gen0;
The code above only assigns the gen1 reference to the same object as gen0. So when you modify gen1, you actually modify gen0 as well... causing inconsistencies in latter iterations. Try this:
gen1 = (string[])gen0.Clone();
Second bug is that int count = 0 should be in the second loop instead of first:
for (int i = 0; i< gen0.Length; i++)
{
// not here
// int count = 0
for (int j = 0; j < gen0[i].Length; j++)
{
// here
int count = 0
...
}
...
}
This way you reset the count for every cell instead of every row.