Balanced Parenthesis

#include <stack>
#include <iostream>


bool areBracketsBalanced(std::string input)
{
    std::stack<char> stackWithBrackets;
    char x;

    for (int i = 0; i < input.length(); i++)
    {
        if (input[i] == '(' || input[i] == '['
            || input[i] == '{')
        {
            stackWithBrackets.push(input[i]);
            continue;
        }

        if (stackWithBrackets.empty())
            return false;

        switch (input[i]) {
        case ')':

            x = stackWithBrackets.top();
            stackWithBrackets.pop();
            if (x == '{' || x == '[')
                return false;
            break;

        case '}':

            x = stackWithBrackets.top();
            stackWithBrackets.pop();
            if (x == '(' || x == '[')
                return false;
            break;

        case ']':

            x = stackWithBrackets.top();
            stackWithBrackets.pop();
            if (x == '(' || x == '{')
                return false;
            break;
        }
    }

    return (stackWithBrackets.empty());
}

int main()
{
    std::string input;
    std::cin >> input;

    if (areBracketsBalanced(input))
        std::cout << "YES";
    else
        std::cout << "NO";
    return 0;
}