#include <cstdlib>
#include <fstream>
#include <iostream>
#include <stack>
#include <string>

typedef std::stack<char> Brackets;

void pushOpeningBrackets(Brackets& opening, char ch)
{
    if (ch == '{')
        opening.push('{');
    else if (ch == '(')
        opening.push('(');
    else if (ch == '[')
        opening.push('[');
}

bool errorsFound(Brackets& stack, char openingBracket, char closingBracket)
{
    // unmatched?
    if (stack.empty())
    {
        std::cerr << "Unmatched " << closingBracket;
        return true;
    }

    char topBracket = stack.top();
    stack.pop();

    // not a match?
    if (topBracket != openingBracket)
    {
        if (topBracket == '{')
            std::cerr << "Expected } but found " << closingBracket;
        else if (topBracket == '(')
            std::cerr << "Expected ) but found " << closingBracket;
        else if (topBracket == '[')
            std::cerr << "Expected ] but found " << closingBracket;

        return true;
    }

    return false;
}

int main()
{
    std::cout << "Enter a text file name: ";
    std::string filename;
    std::getline(std::cin, filename);

    std::ifstream inFile(filename.c_str(), std::ios::in);

    if (!inFile) return EXIT_FAILURE;

    Brackets stack;
    std::string fileLine;

    while (inFile >> fileLine)
    {
        for (char ch : fileLine)
        {
            pushOpeningBrackets(stack, ch);

            if (ch == '}')
            {
                if (errorsFound(stack, '{', '}'))
                {
                    return EXIT_SUCCESS;
                }
            }
            else if (ch == ')')
            {
                if (errorsFound(stack, '(', ')'))
                {
                    return EXIT_SUCCESS;
                }
            }
            else if (ch == ']')
            {
                if (errorsFound(stack, '[', ']'))
                {
                    return EXIT_SUCCESS;
                }
            }
        }
    }

    // checks for missing bracket or full match
    if (!stack.empty())
    {
        char topBracket = stack.top();
        stack.pop();

        if ('{' == topBracket)
            std::cerr << "0";
        else if ('(' == topBracket)
            std::cerr << "0";
        else if ('[' == topBracket)
            std::cerr << "0";
    }
    else
        std::cout << "1";
}