Reversi <Implementation>

#include <bits/stdc++.h>
using namespace std;

int board[8][8];
int mode[8][2]={{1,0},{-1,0},{0,1},{0,-1},{1,1},{-1,-1},{-1,1},{1,-1}};
int m,posx,posy;
bool checknot(int x,int y,int place){
    if(x<0&&x==8&&y<0&&y==8) return false;
    if(board[x][y]==0) return false;
    if(board[x][y]==place){
        posx=x;
        posy=y;
        return true;
    }
    else return checknot(x+mode[m][0],y+mode[m][1],place);
}
void replace(int place){
    posx-=mode[m][0];
    posy-=mode[m][1];
    if(board[posx][posy]!=place){
        board[posx][posy]=place;
    }else return;
    replace(place);
}

int main(){
    int n;
    char c;
    int x,y;
    //White = 2 Black =1;
    board[3][3]=2;
    board[4][4]=2;
    board[3][4]=1;
    board[4][3]=1;
    scanf("%d",&n);
    for(int i=1;i<=n;i++){
        cin >> c >> x;
        x--;
        y=c-'a';
        int u=i%2;
        if(u==0) u=2;
        board[x][y]=u;
        for(int j=0;j<8;j++){
            m=j;
            if(checknot(x+mode[j][0],y+mode[j][1],u)){
                replace(u);
            }
        }
    }
    for(int i=0;i<8;i++){
        for(int j=0;j<8;j++){
            if(board[i][j]==0){
                printf(".");
            }else if(board[i][j]==1){
                printf("X");
            }else{
                printf("O");
            }
        }
        printf("\n");
    }
}