int main() { SList<int> list; list.PushFront(4); list.PushBack(5); list.PushFront(3); list.PushBack(6); list.PushBack(7); list.PushBack(8); list.PushBack(9); list.PushFront(2); list.Insert(1, 11); list.Insert(3, 13); list.Insert(5, 15); list.Insert(20, 20); list.Print(); list.Delete(1); list.Print(); list.Delete(11); list.Print(); list.Delete(7); list.Print(); SList<int> list2; list2.PushBack(1); list2.Print(); list2.Reverse(); list2.Print(); SList<int> list3; list3.PushBack(1); list3.PushBack(2); list3.Print(); list3.Reverse(); list3.Print(); SList<int> list4; list4.PushBack(5); list4.PushBack(4); list4.PushBack(3); list4.PushBack(2); list4.PushBack(1); list4.Print(); list4.Reverse(); list4.Print(); return 0; }
//Convert infix to postfix using shunting yard SList<std::string> XMLParseHelperExpression::ShuntingYard(const SList<std::string>& expressionTokens) { //Stack used with conversion algorithm SList<std::string> stack; //Stores return value SList<std::string> output; for (std::string& item : expressionTokens) { if (!mLegalOperators.ContainsKey(item))//If the item is not an operator, it must be a number and is there for immediately pushed onto the stack { output.PushBack(item); } else if(item == "(")//Check for open parentheses { stack.PushFront(item); } else if (item == ")")//Check for close parentheses { while (stack.Front() != "(")//Add operators to the output until we find the other parentheses { output.PushBack(stack.Front()); stack.PopFront(); if (stack.Size() == 0)//There's a problem if we couldn't find the other parentheses at all { throw std::exception("Expression formed with uneven number of parentheses"); } } stack.PopFront();//Get rid of the open parentheses } else//Otherwise, we're a normal operator. { if (stack.Size() == 0)//We go into the stack if its empty. { stack.PushFront(item); } else//Otherwise we have to compare precedence { //Make sure our operators are actually legal if (!mLegalOperators.ContainsKey(stack.Front()) || !mLegalOperators.ContainsKey(item)) { throw std::exception("Unknown operator put into expression"); } int stackPrecedence = mLegalOperators.Find(stack.Front())->second; int itemPrecedence = mLegalOperators.Find(item)->second; if (itemPrecedence > stackPrecedence)//If the new item has greater precedence, it is put onto the stack { stack.PushFront(item); } else//If the item has less precedence or the same precedence, we put the current operator into the output and then push this item into the stack { output.PushBack(stack.Front()); stack.PushFront(item); } } } } //Push the remaining operators on the stack into the output while (stack.Size() > 0) { output.PushBack(stack.Front()); stack.PopFront(); } return output; }