public static string GetResult(string input)
{
var numStack = new Stack <string>();
var postfixNotation = GetPostfix(input);
char ch;
string num1, num2, interAns;
var num = "";
for (var i = 0; i < postfixNotation.Length; i++)
{
ch = postfixNotation[i];
if (char.IsDigit(ch) || ch == 'i')
{
num += ch;
}
else if (ch == '|')
{
if (num != "")
{
numStack.Push(num);
}
num = "";
}
else
{
var foundComplex = false;
var result = "";
if (num != "")
{
numStack.Push(num);
}
num = "";
num2 = numStack.Pop();
if (numStack.Count == 0)
{
return(num2);
}
num1 = numStack.Pop();
if (!num1.Contains("i") && !num2.Contains("i"))
{
result = SolveTwo(int.Parse(num1), int.Parse(num2), ch) + "";
numStack.Push(result);
continue;
}
/*** Complex part ***/
// If there is already record of complex num and
// usual num e.g. 2+3i
if (num1.Contains("+") || num1.Contains("-") || num2.Contains("+") || num2.Contains("-"))
{
var tmpOpers = new char[] { '+', '-' };
var num1Length = GetAmountNumsInExpression(num1);
var num2Length = GetAmountNumsInExpression(num2);
if (num2Length > num1Length)
{
result = GetOperOnComplexNum(num1, ch, num2);
}
if (num2Length < num1Length)
{
result = GetOperOnComplexNum(num2, ch, num1);
}
if (num2Length == num1Length)
{
var nums = num2.Split(new char[] { '+', '-' });
result = GetOperOnComplexNum(nums[0], ch, num1);
result = GetOperOnComplexNum(nums[1], ch, result);
}
if (result == "")
{
continue;
}
numStack.Push(result);
continue;
}
//Both numbers are complex
if (num2.Contains("i") && num1.Contains("i"))
{
num2 = num2.Substring(0, num2.Length - 1);
num1 = num1.Substring(0, num1.Length - 1);
result = SolveTwo(int.Parse(num1), int.Parse(num2), ch) + "i";
if (result == "0i")
{
continue;
}
}
// One of the numbers is complex and operations are
// multiply, mod or dividing
if (num2.Contains("i") &&
(ch == '*' || ch == '/' || ch == '%'))
{
num2 = num2.Substring(0, num2.Length - 1);
result = SolveTwo(int.Parse(num1), int.Parse(num2), ch) + "i";
}
if (num1.Contains("i") &&
(ch == '*' || ch == '/' || ch == '%'))
{
num1 = num1.Substring(0, num1.Length - 1);
result = SolveTwo(int.Parse(num1), int.Parse(num2), ch) + "i";
}
// One of the numbers is complex and operations are
// plus and minus
if ((num2.Contains("i") || num1.Contains("i")) &&
(ch == '+' || ch == '-'))
{
result = num1 + "" + ch + num2;
}
//Result
numStack.Push(result);
}
}
return(numStack.Pop());
}
public static string GetPostfix(string input)
{
var output = new StringBuilder();
var operStack = new Stack <char>();
var num = "";
for (var i = 0; i < input.Length; i++)
{
var currentChar = input[i];
if (char.IsDigit(input[i]) || input[i] == 'i')
{
num += currentChar;
if (i == input.Length - 1)
{
output.Append(num);
}
continue;
}
switch (currentChar)
{
case '+':
case '-':
if (num != "")
{
output.Append(num);
output.Append("|");
}
num = "";
GotOper(currentChar, 1, operStack, output);
break;
case '*':
case '/':
case '%':
if (num != "")
{
output.Append(num);
output.Append("|");
}
num = "";
GotOper(currentChar, 2, operStack, output);
break;
case '(':
if (num != "")
{
output.Append(num);
output.Append("|");
}
num = "";
operStack.Push(currentChar);
break;
case ')':
if (num != "")
{
output.Append(num);
output.Append("|");
}
num = "";
GotParen(currentChar, operStack, output);
break;
default:
output.Append(currentChar);
break;
}
}
while (operStack.Count != 0)
{
output.Append(operStack.Pop());
}
return(output.ToString());
}