Simplistic-Calculator-v0.6 annotated

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace QuadraticEquationSolver
{
    class Program
    {
        static void Main(string[] args)
        {
            while (true) //loops whole program
            {
                int i = 0; //index of strNumber, used to give value to strNumbers (based on toCalc breakdown)
                int n = 0; //index of strNumber, used to give value to numbers (double array)
                int partNum = 0; //index of operation, used to save toCalc's operation in order
                int digit = 0; //index of toCalc, used to break toCalc down into chars which will, in turn, become part of strings in strNumbers
                int k = 0; //index of numbers & operation, used to find operations of multiplications and division
                int m = 0; //index of multiDivision, used to give priority to multiplication and division
                int h = 0; //index of numbers & operation, used to calculate ans
                double ans = 0; //used in calculations, keeps answer value
                Console.WriteLine("Please enter query:");
                string toCalc = Console.ReadLine();
                string[] strNumbers = new string[toCalc.Length]; //separates numbers from toCalc
                string[] operation = new string[toCalc.Length]; //separates operations from toCalc
                double[] numbers = new double[toCalc.Length]; //converts numbers separated from toCalc by strNumbers to double type
                double[] multiDivision = new double[toCalc.Length]; //runs multiplication and division calculations with priority, used in ans calculations later
                bool isMapped = false; //used to exit toCalc mapping loop
                while (isMapped == false) //loop to map toCalc, runs throu its chars
                {
                    if (toCalc[digit] == '+' || toCalc[digit] == '-' || toCalc[digit] == '*' || toCalc[digit] == '/') //checks if specific toCalc char is an operation
                    {
                        operation[partNum] = Convert.ToString(toCalc[digit]); //saves operation
                        partNum++;
                        digit++; //used so that strNumbers[i] won't keep the operator
                        i++; //changes number of object in numbers array in order to seperate the numbers
                    }
                    strNumbers[i] += toCalc[digit];
                    if (digit == toCalc.Length - 1) //checks if all toCalc chars have been mapped
                    {
                        isMapped = true;
                    }
                    digit++;
                }
                if (i == 0) //checks if toCalc only contains 1 number, if so, prints it
                {
                    Console.WriteLine(strNumbers[0]);
                    continue; //skips rest of current iteration
                }
                while (n <= i) //converts separated numbers from string type to double type
                {
                    numbers[n] = Convert.ToDouble(strNumbers[n]);
                    n++;
                }
                for (k = 1; k < n - 1; k++) //calculates all multiplications and divisions in advance
                {
                    if (operation[k] == "*")
                    {
                        multiDivision[m] = numbers[k] * numbers[k + 1];
                        m++;
                    }
                    if (operation[k] == "/")
                    {
                        multiDivision[m] = numbers[k] / numbers[k + 1];
                        m++;
                    }
                }
                m = 0;
                for (h = 0; h < n - 1; h++) //runs actual calculations
                {
                    if (h == 0 && operation[h + 1] != "*" && operation[h + 1] != "/") //gives ans its initial value if operation[h+1] is of the same priority
                    {
                        if (operation[h] == "+")
                            ans += numbers[h] + numbers[h + 1];
                        if (operation[h] == "-")
                            ans += numbers[h] - numbers[h + 1];
                        if (operation[h] == "/")
                            ans += numbers[h] / numbers[h + 1];
                        if (operation[h] == "*")
                            ans += numbers[h] * numbers[h + 1];
                    }
                    else if (h == 0 && (operation[h + 1] == "*" || operation[h + 1] == "/")) //gives ans its initial value if operation[h+1] is of higher priority
                    {
                        if (operation[h] == "+")
                            ans += numbers[h] + multiDivision[m];
                        if (operation[h] == "-")
                            ans += numbers[h] - multiDivision[m];
                        if (operation[h] == "/")
                            ans += numbers[h] / multiDivision[m];
                        if (operation[h] == "*")
                            ans += numbers[h] * multiDivision[m];
                        h++;
                        m++;
                    }
                    else if (h != 0)
                    {
                        if (operation[h] == "+" || operation[h] == "-") //checks operation
                        {
                            if (operation[h + 1] != "*" && operation[h + 1] != "/") //runs if there is no need to give priority to multiDivision
                            {
                                if (operation[h] == "+")
                                    ans += numbers[h + 1];
                                if (operation[h] == "-")
                                    ans -= numbers[h + 1];
                            }
                            if (operation[h + 1] == "*" || operation[h + 1] == "/") //runs if there is a need to give priority to multiDivision
                            {
                                if (operation[h] == "+")
                                    ans += multiDivision[m];
                                if (operation[h] == "-")
                                    ans -= multiDivision[m];
                                h++;
                                m++;
                            }
                        }
                    }
                }
                  Console.WriteLine(ans); //prints result
            }
        }
    }
}