bool Maze::traverse() { //DO THIS //complete several sections in this method bool done = false; //assume we are not done unless proven otherwise StackLinked<Cell> stack; maze->setElement(1, 1, TRIED); gui->update(); Cell* start_cell = new Cell(1, 1); stack.push(start_cell); //start from the top left corner while(!stack.isEmpty()) { Cell* top_cell = processBackTrack(&stack); if (top_cell == NULL) break; //no solution (back tracked all the way to the beginning) //call a method in the Cell class to give you a new Cell in a new direction relative to top_cell (initially, DOWN) //DO THIS Cell* curr_cell = top_cell -> nextCell(); //does this new Cell solve the maze? done = isSolved(curr_cell, &stack); if (done) break; //DO THIS //get the row and col from curr_cell int row = curr_cell -> getRow(); int col = curr_cell -> getCol(); double element = maze -> getElement(row, col); //check that the current cell corresponds to SPACE, otherwise delete it if (element == SPACE) { //update the cell to TRIED //put the cell on the stack (move forward through the maze) maze -> setElement(row, col, TRIED); stack.push(curr_cell); Sleep(75); //slow down the maze traversal gui->update(); } else //look for a different route { //DO THIS //delete the cell delete curr_cell; } } //did we make it to the bottom right? if (done) { processSolution(&stack); } else { cout << "No solution." << endl; } return done; }
double calculatePostfixExpression(char* expression) { // variables int ndx = 0; char current_char = char(4); StackLinked<double> C; StackLinked<double>* contents = new StackLinked<double>; double operand1 = -8.88; // arbitrary values for garbage double operand2 = -8.88; // clearing and debugging double result = -8.88; // calculate the expression for(ndx = 0; ndx < MAX_EXPRESSION; ndx++) { // extract item from expression current_char = expression[ndx]; // take appropriate action switch(current_char) { case '\0': // stop processing when \0 is encountered ndx = MAX_EXPRESSION; // this will break loop break; // ignore whitespace case ' ': // do nothing break; // store numbers in stack case '0': case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': contents->push( double(current_char - '0') ); break; // perform specified operations case '+': // gather operands operand2 = contents->pop(); operand1 = contents->pop(); // do the math result = operand1 + operand2; // store the result contents->push(result); break; case '-': // gather operands operand2 = contents->pop(); operand1 = contents->pop(); // do the math result = operand1 - operand2; // store the result contents->push(result); break; case '*': // gather operands operand2 = contents->pop(); operand1 = contents->pop(); // do the math result = operand1 * operand2; // store the result contents->push(result); break; case '/': // gather operands operand2 = contents->pop(); operand1 = contents->pop(); // do the math result = operand1 / operand2; // store the result contents->push(result); break; default: // ignore all other characters, i.e. do nothing break; } } // save the result before returning dynamic memory result = contents->pop(); // return dynamic memory delete contents; contents = NULL; // return the result return result; }