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expression must be a modifiable lvalue error

BJzero (15)
i have a project i need to write a tic tac toe game using arrays..
i've managed to write everything but i'm having problem when writing the function win() to determine who has won...
i have a
 
 
char square[3][3]={' ',' ',' ',' ',' ',' ',' ',' ',' '};

im writing this:

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int win()            
{int pwin=5;


if(square[0][0]=='X' &&square[0][1]=='X' && square[0][2]=='X')               
    pwin= 1;

    else if(square[1][0]=='X' &&square[1][1]=='X' && square[1][2]='X')
    pwin=1;

    else if(square[2][0]=='X' &&square[2][1]=='X' && square[2][2]='X')
    pwin=1;

    else if(square[0][0]=='X' &&square[1][0]=='X' && square[2][0]='X')
    pwin=1;

    else if(square[0][1]=='X' &&square[1][1]=='X' && square[2][1]='X')
    pwin=1;

    else if(square[0][2]=='X' &&square[1][2]=='X' && square[2][2]='X')
    pwin=1;

    else if(square[0][0]=='X' &&square[1][1]=='X' && square[2][2]='X')
    pwin=1;

    else if(square[0][2]=='X' &&square[1][1]=='X' && square[2][0]='X')
    pwin=1;

else if(square[0][0]=='O' &&square[0][1]=='O' && square[0][2]=='O')               
    pwin= 2;

    else if(square[1][0]=='O' &&square[1][1]=='O' && square[1][2]='O')
    pwin=2;

    else if(square[2][0]=='O' &&square[2][1]=='O' && square[2][2]='O')
    pwin=2;

    else if(square[0][0]=='O' &&square[1][0]=='O' && square[2][0]='O')
    pwin=2;

    else if(square[0][1]=='O' &&square[1][1]=='O' && square[2][1]='O')
    pwin=2;

    else if(square[0][2]=='O' &&square[1][2]=='O' && square[2][2]='O')
    pwin=2;

    else if(square[0][0]=='O' &&square[1][1]=='O' && square[2][2]='O')
    pwin=2;

    else if(square[0][2]=='O' &&square[1][1]=='O' && square[2][0]='O')
    pwin=2;

   else if (square[0][0] != ' ' && square[0][1] != ' ' && square[0][2] != ' '           && square[1][0] != ' ' &&square[1][1] != ' '
    && square[1][2] != ' ' && square[2][0] != ' ' && square[2][1] != ' ' && square[2][2] != ' ')
    pwin=0;

else
pwin= -1;

return pwin;

in function main i wrote this 
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     i=win();
    if(i==1)
    
	cout<<"player 1 won";
    if(i==2)
        cout<<"computer won";
    if(i==0)
        cout<<"Game draw";

now my problem is that im having an expression must be a modifiable lvalue error in win() function after the first if statement.... how to solve it?
thank you
Last edited on
Peter87 (11175)
You are using = (assignment) instead of == (equal to comparison) in a few places.
BJzero (15)
thank you
vlad from moscow (6539)
As Peter87 pointed out using the assignment operator instead of the comparision operator and due to priorities of operations the statement

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    else if(square[1][0]=='X' &&square[1][1]=='X' && square[1][2]='X')
    pwin=1;


is interpretated by the compiler as

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    else if( ( square[1][0]=='X' &&square[1][1]=='X' && square[1][2] ) = 'X' )
    pwin=1;


that is you are trying to assign 'X' to the expression ( square[1][0]=='X' &&square[1][1]=='X' && square[1][2] )
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