Interview Question for Software Engineer at Research in Motion:

generally, use a loop:

char[][] Xs = new char[MAX_ROW][MAX_COL];

for(int row = 0; row < MAX_COL / 2; row++) {
          Xs[row][row] = 'x' ;
          Xs[row][MAX_COL - row] = 'x' ;
}

Xs[MAX_COL / 2][MAX_COL / 2] = 'x' ;

for(int row = MAX_COL / 2 + 1; row < MAX_COL; row++) {
          Xs[row][row] = 'x' ;
          Xs[row][MAX_COL - row] = 'x' ;
}

draw(Xs);