A sample Tic Tac Toe program I made without a GUI, when I started with C++

Tic-Tac -Toe C++

#include <iostream>

using namespace std;

int main()
{

const int ROWS=3;
const int COLUMNS=3;
char board[ROWS][COLUMNS]={{'1','2','3'},
                           {'4','5','6'},
                           {'7','8','9'}};

int X;
int O;
bool win;


cout<<"\tWelcome to Tic-tac Toe!\n";
cout<<"\n\nThis is a two player game that simulates the classic";
cout<<"\nTic tac toe game. Decided who is 'X' and who is '0'. X always goes first.\n";
cout<<"Enter the corresponding number to input your 'X' or '0'\n";

cout<<"\nThe board is now\n";

for(int i=0;i<ROWS;++i){

    for(int j=0;j<COLUMNS;++j){
        cout<<board[i][j];
    }
    cout<<endl;
}






do{


bool valid=false;

cout<<"\nPlayer one's Turn";
cin>>X;


       switch(X){

case 1: if(board[0][0]!='O'){
    board[0][0]='X';
} else {
cout<<"You can't move there\n";
continue;
}
break;

case 2: if(board[0][1]!='O'){
    board[0][1]='X';
} else {
 cout<<"You can't move there.\n";
 continue;
}
break;

case 3:if(board[0][2]!='O'){
    board[0][2]='X';
} else {
 cout<<"You can't move there.\n";
 continue;
}
break;


case 4: if(board[1][0]!='O'){
    board[1][0]='X';
} else {
 cout<<"You can't move there.\n";
 continue;
}
break;


case 5:if(board[1][1]!='O'){
    board[1][1]='X';
} else {
 cout<<"You can't move there.\n";
 continue;
}
break;



case 6:if(board[1][2]!='O'){
    board[1][2]='X';
} else {
 cout<<"You can't move there.\n";
 continue;
}
break;


case 7: if(board[2][0]!='O'){
    board[2][0]='X';
} else {
 cout<<"You can't move there.\n";
 continue;
}
break;



case 8:if(board[2][1]!='O'){
    board[2][1]='X';
} else {
 cout<<"You can't move there.\n";
 continue;
}
break;




case 9:if(board[2][2]!='O'){
    board[2][2]='X';
} else {
 cout<<"You can't move there.\n";
 continue;
}
break;


default: cout<<"Please select a value 1-9.\n";
continue;


}

for(int i=0;i<ROWS;++i){

    for(int j=0;j<COLUMNS;++j){
        cout<<board[i][j];
    }
    cout<<endl;
}


if(board[0][0]=='X'&& board[0][1]=='X'&& board[0][2]=='X' || board[1][0]=='X'&& board[1][1]=='X' && board[1][2]=='X' || board[2][0]=='X' && board[2][1]=='X' && board[2][2]=='X' || board[0][0]=='X' && board[1][0]=='X' && board[2][0]=='X' || board[0][1]=='X' && board[1][1]=='X' && board[2][1]=='X' || board[0][2]=='X' && board[1][2]=='X' && board[2][2]=='X' || board[0][0]=='X' && board[1][1]=='X' && board[2][2]=='X' || board[2][0]=='X' && board[1][1]=='X' && board[0][2]=='X' )
{

 win=true;
    cout<<"Player 1 wins!\n";

 break;


}




if((board[0][0]=='X'||board[0][0]=='O')&&(board[0][1]=='X'||board[0][1]=='O')&&(board[0][2]=='X'|| board[0][2]=='O')&&(board[1][0]=='X'||board[1][0]=='O')&&(board[1][1]=='X'||board[1][1]=='O')&&(board[1][2]=='X'||board[1][2]=='O')&&(board[2][0]=='X'||board[2][0]=='O')&&(board[2][1]=='X'||board[2][1]=='O')&&(board[2][2]=='X'||board[2][2]=='O')){

    cout<<"A draw!\n";
}




while(valid!=true){


cout<<"\nNow player 2 goes";
cin>>O;



switch(O){

case 1: if(board[0][0]!='X'){
    board[0][0]='O';
    valid=true;
} else {
cout<<"You can't move there\n";
continue;
}
break;

case 2: if(board[0][1]!='X'){
    board[0][1]='O';
     valid=true;
} else {
 cout<<"You can't move there.\n";
 continue;
}
break;

case 3:if(board[0][2]!='X'){
    board[0][2]='O';
     valid=true;
} else {
 cout<<"You can't move there.\n";
 continue;
}
break;


case 4: if(board[1][0]!='X'){
    board[1][0]='O';
     valid=true;
} else {
 cout<<"You can't move there.\n";
 continue;
}
break;


case 5:if(board[1][1]!='X'){
    board[1][1]='O';
     valid=true;
} else {
 cout<<"You can't move there.\n";
 continue;
}
break;



case 6:if(board[1][2]!='X'){
    board[1][2]='O';
     valid=true;
} else {
 cout<<"You can't move there.\n";
 continue;
}
break;


case 7: if(board[2][0]!='X'){
    board[2][0]='O';
     valid=true;
} else {
 cout<<"You can't move there.\n";
 continue;
}
break;



case 8:if(board[2][1]!='X'){
    board[2][1]='O';
     valid=true;
} else{
 cout<<"You can't move there.\n";
 continue;
}
break;




case 9:if(board[2][2]!='X'){
    board[2][2]='O';
     valid=true;
} else {
 cout<<"You can't move there.\n";
 continue;
}
break;


default: cout<<"Please select a value 1-9.\n";
continue;


}
}


for(int i=0;i<ROWS;++i){

    for(int j=0;j<COLUMNS;++j){
        cout<<board[i][j];
    }
    cout<<endl;
}


//Winning statements 7 ways to win a tic tac toe game







if(board[0][0]=='O' && board[0][1]=='O' && board[0][2]=='O' || board[1][0]=='O' && board[1][1]=='O' && board[1][2]=='O' || board[2][0]=='O' && board[2][1]=='O' && board[2][2]=='O' || board[0][0]=='O' && board[1][0]=='O' && board[2][0]=='O' || board[0][1]=='O' && board[1][1]=='O' && board[2][1]=='O' || board[0][2]=='O' && board[1][2]=='O' && board[2][2]=='O' || board[0][0]=='O' && board[1][1]=='O' && board[2][2]=='O' || board[2][0]=='O' && board[1][1]=='O' && board[0][2]=='O' )
{

 win=true;
    cout<<"Player 2 wins!\n";

    break;


}

if((board[0][0]=='X'||board[0][0]=='O')&&(board[0][1]=='X'||board[0][1]=='O')&&(board[0][2]=='X'|| board[0][2]=='O')&&(board[1][0]=='X'||board[1][0]=='O')&&(board[1][1]=='X'||board[1][1]=='O')&&(board[1][2]=='X'||board[1][2]=='O')&&(board[2][0]=='X'||board[2][0]=='O')&&(board[2][1]=='X'||board[2][1]=='O')&&(board[2][2]=='X'||board[2][2]=='O')){

    cout<<"A draw!\n";
}








}while(win!=true);


return 0;

}