StackLinked<DataType>::StackLinked(const StackLinked& other){
if(this != other){
while(!other->isEmpty()){
this->push(other->pop());
}
}
}
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;
}
