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Help under standing parts of code

leeffm (19)
I need help understanding these parts of my code, i wrote it for school but dont know what some parts are for.

I dont know what bool does , or (int m)
bool MoveIsValid (int m);

I dont know what (Move) does
while (MoveIsValid (Move) != true);

I dont know what break; does
break;

again bool and (int m) , and i dont knwo what return does
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bool MoveIsValid (int m) {
	
	if (Board[m] != 'x' && Board[m] != 'o'){
		
		return true;
	}
		else {
			
			return false;
		}
}


Why return 1 or 2 or 0
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int WhoWon () {
	
	if (Board[0] == Board[1] && Board[1] == Board[2]) {
		
		if (Board[0] == 'x') {
			
			return 1;
		}
			else {
				
				return 2;
			}
	}

	if (Board[3] == Board[4] && Board[4] == Board[5]) {
		
		if (Board[3] == 'x') {
			
			return 1;
		}
			else {
				
				return 2;
			}
	}

	if (Board[6] == Board[7] && Board[7] == Board[8]) {
		
		if (Board[6] == 'x') {
			
			return 1;
		}
			else {
				
				return 2;
			}
	}

	if (Board[0] == Board[3] && Board[3] == Board[6]) {
		
		if (Board[0] == 'x') {
			
			return 1;
		}
			else {
				
				return 2;
			}
	}

	if (Board[1] == Board[4] && Board[4] == Board[7]) {
		
		if (Board[1] == 'x') {
			
			return 1;
		}
			else {
				
				return 2;
			}
	}

	if (Board[2] == Board[5] && Board[5] == Board[8]) {
		
		if (Board[2] == 'x') {
			
			return 1;
		}
			else {
				
				return 2;
			}
	}

	if (Board[0] == Board[4] && Board[4] == Board[8]) {
		
		if (Board[0] == 'x') {
			
			return 1;
		}
			else {
				
				return 2;
			}
	}

	if (Board[2] == Board[4] && Board[4] == Board[6]) {
		
		if (Board[2] == 'x') {
			
			return 1;
		}
			else {
				
				return 2;
			}
	}
	return 0;
}


i am trying to practice by re writing theese codes from school projects without looking alot but i didnt understand parts of them in the first place.

Thanks in advandce!

This is the whole Tic_Tac_Toe program
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// Tic_Tac_Toe by Liberty Satonica

// Include libraries
#include <iostream>
#include <string>

// use standerd namespace
using namespace std;

// Declare global values
char Board[9];

// Declare the funtions
void ShowBoard ();
bool MoveIsValid (int m);
int WhoWon (); //Returns 0 if noone won, 1 if player 1 won, and 2 if player 2 won.
int Total_Moves = 0;

void main () {

	// Declare local variables
	string Player_1_Name;
	string Player_2_Name;
	int Whose_Turn = 1; // 1 means it's player 1's turn , 2 means 2's turn
	int Move; // Stores where the player wants to move.

	// Assign values to playing board
	Board [0] = '0';
	Board [1] = '1';
	Board [2] = '2';
	Board [3] = '3';
	Board [4] = '4';
	Board [5] = '5';
	Board [6] = '6';
	Board [7] = '7';
	Board [8] = '8';

	// get player names
	cout << "Player 1: Please enter your name." << endl;
	cin >> Player_1_Name;
	cout << "Player 2: Please enter your name." << endl;
	cin >> Player_2_Name;
	
	while (WhoWon () == 0 && Total_Moves < 9) {
		// Do this until the player chooses a valid move
		do {


			// Show The Bored
			ShowBoard () ;

			// Tell which player to move
			if (Whose_Turn == 1){
				
				cout << Player_1_Name << ": It's your turn." << endl;
			}
				else {
					
					cout << Player_2_Name << ": It's your turn." << endl;
				}

			// Get the move.
			cout << "Enter the number of the spot you'd like to move" << endl;
			cin >> Move;
		} while (MoveIsValid (Move) != true);

		// Add 1 to Total_Moves
		Total_Moves++;

		// Change whose turn it is
		switch (Whose_Turn) {
			
			case (1): {
				
				Board[Move] = 'x';
				Whose_Turn = 2;
				break;
			}
			case (2): {
				
				Board[Move] = 'o';
				Whose_Turn = 1;
			}
		}
	}

	// Show the board
	ShowBoard ();
	
	if (WhoWon () == 1) {
		
		cout << Player_1_Name << " has won the game!" << endl;
	}
		else if (WhoWon () == 2) {
			
			cout << Player_2_Name << " has won the game!" << endl;
		}
			else {
				
				cout << "It's a tie game!" << endl;
			}

		system ("pause");
}

void ShowBoard () {

	cout << endl;
	cout << Board[0]<< " | " << Board[1]<< " | " << Board[2] << endl;
	cout << "--+---+--" << endl;
	cout << Board[3]<< " | " << Board[4]<< " | " << Board[5] << endl;
	cout << "--+---+--" << endl;
	cout << Board[6]<<" | " << Board[7]<<" | " << Board[8] << endl;
	cout << endl;
}

bool MoveIsValid (int m) {
	
	if (Board[m] != 'x' && Board[m] != 'o'){
		
		return true;
	}
		else {
			
			return false;
		}
}

int WhoWon () {
	
	if (Board[0] == Board[1] && Board[1] == Board[2]) {
		
		if (Board[0] == 'x') {
			
			return 1;
		}
			else {
				
				return 2;
			}
	}

	if (Board[3] == Board[4] && Board[4] == Board[5]) {
		
		if (Board[3] == 'x') {
			
			return 1;
		}
			else {
				
				return 2;
			}
	}

	if (Board[6] == Board[7] && Board[7] == Board[8]) {
		
		if (Board[6] == 'x') {
			
			return 1;
		}
			else {
				
				return 2;
			}
	}

	if (Board[0] == Board[3] && Board[3] == Board[6]) {
		
		if (Board[0] == 'x') {
			
			return 1;
		}
			else {
				
				return 2;
			}
	}

	if (Board[1] == Board[4] && Board[4] == Board[7]) {
		
		if (Board[1] == 'x') {
			
			return 1;
		}
			else {
				
				return 2;
			}
	}

	if (Board[2] == Board[5] && Board[5] == Board[8]) {
		
		if (Board[2] == 'x') {
			
			return 1;
		}
			else {
				
				return 2;
			}
	}

	if (Board[0] == Board[4] && Board[4] == Board[8]) {
		
		if (Board[0] == 'x') {
			
			return 1;
		}
			else {
				
				return 2;
			}
	}

	if (Board[2] == Board[4] && Board[4] == Board[6]) {
		
		if (Board[2] == 'x') {
			
			return 1;
		}
			else {
				
				return 2;
			}
	}
	return 0;
}


OFF TOPIC NOTE:

this is my program i was writing so far( i was trying to make a choice between 1 player or 2 player) 

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/* Practice 

Tic_Tac_Toe

by

liberty 
*/

#include <iostream>
#include <String>

using namespace std;

// Declare Global variables
char Board[9];

// Declare Functions
void ShowBoard ();

int main () {

    // declare local variables
	int GameType;
	string Player1_Name;
	string Player2_Name;
	int WhoseTurn = 1;
	int Move;

	// Asign values to playing board
	Board [0] = '0';
	Board [1] = '1';
	Board [2] = '2';
	Board [3] = '3';
	Board [4] = '4';
	Board [5] = '5';
	Board [6] = '6';
	Board [7] = '7';
	Board [8] = '8';
	
	// Ask for Human VS. Human Or Human VS. Computer
	cout << "Would you like to play against a Human or the Computer?" << endl;
	cout << "Press 1 for Human or 2 for Computer!" << endl;
	cin >> GameType;
	
	while (GameType == 1) {
    
    // Get Player Names
    cout << "Player 1: Please enter your name!" << endl;
    cin >> Player1_Name;
    cout << "Player 2: Please enter your name!" << endl;
    cin >> Player2_Name;
    
    ShowBoard ();
    
        // Tell Which Player to move
        if (WhoseTurn == 1) {
               
          cout << Player1_Name << ": It's your turn!" << endl;     
               
        } 
          else {
          
          cout << Player2_Name << ": It's your turn!" << endl;
          
          } 
          
          // Get the Player[s] move
          cout << "Enter the number of the spot you want to move" << endl;
          cin >> Move;
          
    // Change whose turn it is
	switch (WhoseTurn) {
			
	  case (1): {
				
	   Board[Move] = 'x';
	   WhoseTurn = 2;
	   break;
	   }
             case (2): {
             
                Board[Move] = 'o';
                WhoseTurn = 1;
             }    
    
    }
	
	system("PAUSE");

    }
}

 void ShowBoard () {
     cout << endl;
     cout << Board[0] << " | " << Board[1] << " | " << Board[2] << endl;
	 cout << "--+---+--" << endl;
	 cout << Board[3] << " | " << Board[4] << " | " << Board[5] << endl;
	 cout << "--+---+--" << endl;
	 cout << Board[6] << " | " << Board[7] << " | " << Board[8] << endl;
	 cout << endl;
  }
Stewbond (2827)
I dont know what bool does , or (int m)
bool MoveIsValid (int m);

This is a function header. It means that you can write MoveIsValid() and the code in this function will be run. You need to provide an argument with an integer type in the brackets. The functions will return a bool.

I dont know what (Move) does
while (MoveIsValid (Move) != true);
Here you are putting an integer with the name "Move" into MoveIsValid. If the move is valid, then the function will return true and you will exit the while loop.

I dont know what break; does
break will get you out of a loop. so in the following example, the IF condition will exit the while loop immediately.
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while (true)
{
    if(true) break;
}


i dont knwo what return does

return will return the value. Think of it like this. When you call MoveIsValid(1), you are going to run the code in that function. When the code is done running, it effectively replaces MoveIsValid(1) with true or false depending on what is done in the function.

This link will help you:
http://cplusplus.com/doc/tutorial/functions/
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