#include #include #include using namespace std; template class Stack : public stack { public: T pop() { T tmp = top(); stack::pop(); return tmp; } }; class Cell { public: Cell(int i = 0, int j = 0) { x = i; y = j; } bool operator== (const Cell& c) const { return x == c.x && y == c.y; } private: int x, y; friend class Maze; }; class Maze { public: Maze(); void exitMaze(); private: Cell currentCell, exitCell, entryCell; const char exitMarker, entryMarker, visited, passage, wall; Stack mazeStack; char **store; // array of strings; void pushUnvisited(int,int); int rows, cols; friend ostream& operator<< (ostream& out, const Maze& maze) { for (int row = 0; row <= maze.rows+1; row++) out << maze.store[row] << endl; out << endl; return out; } }; Maze::Maze() : exitMarker('e'), entryMarker('m'), visited('.'), passage('0'), wall('1') { Stack mazeRows; char str[80], *s; int col, row = 0; cout << "Enter a rectangular maze using the following " << "characters:\nm - entry\ne - exit\n1 - wall\n0 - passage\n" << "Enter one line at at time; end with Ctrl-z:\n"; while (cin >> str) { row++; cols = strlen(str); s = new char[cols+3]; // two more cells for borderline columns; mazeRows.push(s); strcpy(s+1,str); s[0] = s[cols+1] = wall; // fill the borderline cells with 1s; s[cols+2] = '\0'; if (strchr(s,exitMarker) != 0) { exitCell.x = row; exitCell.y = strchr(s,exitMarker) - s; } if (strchr(s,entryMarker) != 0) { entryCell.x = row; entryCell.y = strchr(s,entryMarker) - s; } } rows = row; store = new char*[rows+2]; // create a 1D array of pointers; store[0] = new char[cols+3]; // a borderline row; for ( ; !mazeRows.empty(); row--) { store[row] = mazeRows.pop(); } store[rows+1] = new char[cols+3]; // another borderline row; store[0][cols+2] = store[rows+1][cols+2] = '\0'; for (col = 0; col <= cols+1; col++) { store[0][col] = wall; // fill the borderline rows with 1s; store[rows+1][col] = wall; } } void Maze::pushUnvisited(int row, int col) { if (store[row][col] == passage || store[row][col] == exitMarker) { mazeStack.push(Cell(row,col)); } } void Maze::exitMaze() { int row, col; currentCell = entryCell; while (!(currentCell == exitCell)) { row = currentCell.x; col = currentCell.y; cout << *this; // print a snapshot; if (!(currentCell == entryCell)) store[row][col] = visited; pushUnvisited(row-1,col); pushUnvisited(row+1,col); pushUnvisited(row,col-1); pushUnvisited(row,col+1); if (mazeStack.empty()) { cout << *this; cout << "Failure\n"; return; } else currentCell = mazeStack.pop(); } cout << *this; cout << "Success\n"; } int main() { Maze().exitMaze(); return 0; }