ShuntingYard.cpp

#include "ShuntingYard.h"

double ShuntingYard::getNotation(string &line) {
    stack<double> test;
    stack<string> array;
    string current;
    for (int i = 0; i < line.length(); ++i) {
        check::ifUnary(i, line);
        current = line[i];
        if (check::isNumber(current)) {
            current = getNumber(i, line);
            double elem = calc::toDouble(current);
            test.addElement(elem);
        } else if (check::isOpen(current)) {
            array.addElement(current);
        } else if (check::isClose(current)) {
            pushScope(array, test);
        } else {
            pushOperation(array, current, test);
        }
    }
    takeCashBack(array, test);
    double result = test.getElement();
    return result;
}

void ShuntingYard::pushOperation(stack<string> &array, string &current, stack<double> &test) {
    if (!array.isEmpty()) {
        while (!array.isEmpty()) {
            string temp = array.getElement();
            if (check::getPrecedence(current) <= check::getPrecedence(temp) && !check::getAssociativity(current) ||
                check::getPrecedence(current) < check::getPrecedence(temp) && check::getAssociativity(current)) {
                addOperation(test, temp);
                array.deleteElement();
            }
            else{
                break;
            }
        }
    }
    array.addElement(current);
}


void ShuntingYard::takeCashBack(stack<string> &array, stack<double> &test) {
    while (!array.isEmpty()) {
        string current = array.getElement();
        addOperation(test, current);
        array.deleteElement();
    }
}

void ShuntingYard::pushScope(stack<string> &array, stack<double> &test) {
    while (!array.isEmpty()) {
        string current = array.getElement();
        if (current == "(") {
            array.deleteElement();
            break;
        } else {
            addOperation(test, current);
            array.deleteElement();
        }
    }
}

string ShuntingYard::getNumber(int &start, string &line) {
    string number;
    while (start < line.length()) {
        if (check::isNumber(line[start]) || line[start] == '.')
            number += line[start++];
        else
            break;
    }
    start--;
    return number;
}

void ShuntingYard::addOperation(stack<double> &test, string &oper) {
    double a, b;
    a = test.getElement();
    test.deleteElement();

    if (oper == "m") {
        b = 0;
    } else {
        b = test.getElement();
        test.deleteElement();
    }

    double res = calc::operation(a, b, oper);
    test.addElement(res);
}