Lab5Lingvo

// ArithmeticExpr.cpp: определяет точку входа для консольного приложения.
//

#include "stdafx.h"
#include <iostream>
#include <string>
#include <vector>

using namespace std;

char signs[] = { '*', '/', '+', '-', '=' };

bool isOperator(char symb)
{
    if (symb == '+' || symb == '-' || symb == '*' || symb == '/' || symb == '(' || symb == ')')
        return true;
    else
        return false;
}
void reverse(string& input)
{
    string output;
    for (int i = input.length() - 1; i > -1; i--)
        output = output + input[i];
    input = output;
}
int getPrcd(char symb)
{
    if (symb == '*' || symb == '/')
        return 4;
    if (symb == '+' || symb == '-')
        return 2;
    if (symb == '(' || symb == ')' || symb == '#')
        return 1;
}
void infixToPrefix(string infix, string& prefix)
{
    int i, j = 0;
    char symb;
    vector<char> opArray;
    opArray.push_back('#');
    reverse(infix);
    for (i = 0; i < infix.length(); i++)
    {
        symb = infix[i];
        if (isOperator(symb) == 0)
        {
            prefix = prefix + symb;
            j++;
        }
        else
        {
            if (symb == ')')
            {
                opArray.push_back(symb);
            }
            else if (symb == '(')
            {
                while (opArray.back() != ')')
                {
                    prefix = prefix + opArray.back();
                    opArray.pop_back();
                    j++;
                }
                opArray.pop_back();
            }
            else
            {
                if (getPrcd(opArray.back()) <= getPrcd(symb))
                {
                    opArray.push_back(symb);
                }
                else
                {
                    while (getPrcd(opArray.back()) >= getPrcd(symb))
                    {
                        prefix = prefix + opArray.back();
                        opArray.pop_back();
                        j++;
                    }
                    opArray.push_back(symb);
                }
            }
        }
    }
    while (opArray.back() != '#')
    {
        prefix = prefix + opArray.back();
        opArray.pop_back();
        j++;
    }
}
void genCode(string txt)
{
    string code;
    string leftop;
    string rightop;
    string curCode;
    string op;
    int i = 0;
    while (txt[i] != '\0')
    {
        if (txt[i] == '=')
        {
            code = txt[i + 1];
            code = "mov " + code + ",ax\n";
        }
        else if (isOperator(txt[i]))
        {
            if (!isOperator(txt[i + 1]) && !isOperator(txt[i + 2]))
            {
                leftop = txt[i + 1];
                rightop = txt[i + 2];
                switch (txt[i])
                {
                case '+': op = "add "; break;
                case '-': op = "sub "; break;
                case '*': op = "mul "; break;
                case '/': op = "div "; break;
                default:
                    break;
                }
                curCode = "mov eax, " + leftop + "\n" + op + "eax, " + rightop;
                code = curCode + "\n" + code;
            }
            if (isOperator(txt[i + 1]) && !isOperator(txt[i + 2]))
            {

            }
        }
    }
    cout << code;
}

int main()
{
    string input;
    string output;
    cin >> input;
    infixToPrefix(input, output);
    reverse(output);
    output = "=A" + output;
    cout << output << endl;
    genCode(output);
    return 0;
}