print a chess board graphic of the solutions to 8 queens problem with filling the C++ program below:

#include  #include  using namespace std; bool ok(int q[], int c) { for (int i = 0; i < c; ++i) if (q[i] == q[c] || abs(q[i] - q[c]) == c - i) return false; return true; } void print(int q[]) { static int solution = 0; int i, j, k, l; typedef char box[5][7]; // box is now a data type: a 5x7 2D array of characters box bb, wb, *board[8][8]; // bb and wb are boxes (5x7 arrays). board is an 8x8 array of pointers to boxes. // You don't have to clean up the board after printing, because it's not static, // so it'll be reinitialized the next time you call the funtion. // Fill in bb (black box) and wb (white box). They each represent a square of the chessboard. // You only need to create one of each, since the chessboard can contain many pointers to the same box. for (i=0; i<5; i++) for (j=0; j<7; j++) { bb[i][j] = ' '; wb[i][j] = char(219); } // Create 2 more boxes to represent the queens, by drawing a picture of each queen in the 2D array. static box bq = { {char(219),char(219),char(219),char(219),char(219),char(219),char(219)}, {char(219),' ' ,char(219),' ' ,char(219),' ' ,char(219)}, {char(219),' ' ,' ' ,' ' ,' ' ,' ' ,char(219)}, {char(219),' ' ,' ' ,' ' ,' ' ,' ' ,char(219)}, {char(219),char(219),char(219),char(219),char(219),char(219),char(219)} }; static box wq = { {' ' ,' ' ,' ' ,' ' ,' ' ,' ' ,' ' }, {' ' ,char(219),' ' ,char(219),' ' ,char(219),' ' }, {' ' ,char(219),char(219),char(219),char(219),char(219),' ' }, {' ' ,char(219),char(219),char(219),char(219),char(219),' ' }, {' ' ,' ' ,' ' ,' ' ,' ' ,' ' ,' ' } }; // Fill board with pointers to bb and wb in alternate positions. for(i=0; i<8; i++) for(j=0; j<8; j++) if((i+j)%2 == 0) board[i][j] = &wb; else board[i][j] = &bb; // Set up the current solution on the chessboard by placing pointers to bq and wq in the appropriate squares. // Place black queens on white squares and white queens on black squares, so that you will be able to see them when printing. // Write the code. cout << "Solution #" << ++solution << ": "; // Print upper border for (i=0; i<7*8; i++) cout << '_'; cout << " "; // Print the board for (i=0; i<8; i++) // for each board row for (k=0; k<5; k++) { // for each box row cout << char(179); for (j=0; j<8; j++) // for each board column for (l=0; l<7; l++) // for each box column // board[i][j] is the box pointer in the ith row, jth column of the board. // *board[i][j] is the box being pointed to. // (*board[i][j])[k][l] is the kth row, lth column of the box. cout << (*board[i][j])[k][l]; cout << char(179) << " "; } // Print lower border cout << " "; for (i=0; i<7*8; i++) cout << char(196); cout << " "; } void next(int q[], int c) { if (c == 8) print(q); else for (q[c] = 0; q[c] < 8; ++q[c]) if (ok(q, c)) next(q, c+1); } int main() { int q[8]; next(q, 0); return 0; }