Логика для игры крестики нолики

#include<iostream>
#include<cstdlib>
#include<stdlib.h>
using namespace std;
 
 
 
 
char square[11]={'0','1','2','3','4','5','6','7','8','9','\0'};
void board();
int win();
 
 
 
main()
{
setlocale(LC_ALL, "Russian"); 
 
   char playagain='y';
   while(playagain=='y')
   {
    cout<<"Dobro pojalovat!\n\n\n"<<endl;
    int player=1;
    int i,poz;
    char mark;
 
    do
    {
 
     board();
     player=(player%2)?1:2;
     cout<< endl;
      
            
              cout<<"Igrok  "<<player<<" vvedite poziciy: ";cin >>poz;                
             
       
     mark=(player==1)?'X':'O';
     
 
     if(poz==1 && square[1]=='1')
       square[1]=mark;
 
     else if (poz == 2 && square[2] == '2')
 
            square[2] = mark;
        else if (poz == 3 && square[3] == '3')
 
            square[3] = mark;
        else if (poz == 4 && square[4] == '4')
 
            square[4] = mark;
        else if (poz == 5 && square[5] == '5')
 
            square[5] = mark;
        else if (poz == 6 && square[6] == '6')
 
            square[6] = mark;
        else if (poz == 7 && square[7] == '7')
 
            square[7] = mark;
        else if (poz == 8 && square[8] == '8')
 
            square[8] = mark;
        else if (poz == 9 && square[9] == '9')
 
            square[9] = mark;
           
        else
        {
            cout<<"\n Nepravilnii vvod! \n\n";
            player--;
            cout <<endl;
            
 
        }
         system ("cls");
        i=win();
        player++;
    }while(i==-1);
    board();
    if(i==1)
    {
   cout <<endl;
    cout<<"Igrok"<<--player<<" pobedil!";}
    if(i==0)
    {
    cout<<endl;
    cout<<"Igra zakonchilas v nichjy !" <<endl;
    player--;}
cout <<endl;
 
system("pause");
return 0;
 
}
 
}
 
int win()
{
    if(square[1]==square[2]&&square[2]==square[3])
    return 1;
 
    else if(square[4]==square[5]&&square[5]==square[6])
    return 1;
 
    else if(square[7]==square[8]&&square[8]==square[9])
    return 1;
 
    else if(square[1]==square[4]&&square[4]==square[7])
    return 1;
 
    else if(square[2]==square[5]&&square[5]==square[8])
    return 1;
 
    else if(square[3]==square[6]&&square[6]==square[9])
    return 1;
 
    else if(square[1]==square[5]&&square[5]==square[9])
    return 1;
 
    else if(square[3]==square[5]&&square[5]==square[7])
    return 1;
 
   else if (square[1] != '1' && square[2] != '2' && square[3] != '3' && square[4] != '4'&&square[5] != '5'
    && square[6] != '6' && square[7] != '7' && square[8] != '8' && square[9] != '9')
    return 0;
 
else
return -1;
 
}
 
void board()
{
 
 
    cout<<"\tKrestiki Noliki\t\t\n\n";
    cout<<"Igrok 1(X)  ,  Igrok 2(O)\n\n";
    cout<<square[1]<<"|"<<square[2]<<"|"<<square[3]<<endl;
    cout<<"-----"<<endl;
    cout<<square[4]<<"|"<<square[5]<<"|"<<square[6]<<endl;
    cout<<"-----"<<endl;
    cout<<square[7]<<"|"<<square[8]<<"|"<<square[9]<<endl;
 
 
}