Valid parentheses with a stack, visualized

text = "{[()()]}"
stack = []
pairs = {")": "(", "]": "[", "}": "{"}
balanced = True

for ch in text:
    if ch in "([{":
        stack.append(ch)
    else:
        if not stack or stack.pop() != pairs[ch]:
            balanced = False
            break

print(balanced and len(stack) == 0)

#include <iostream>
#include <stack>
#include <string>
using namespace std;

int main() {
    string text = "({[]})";
    stack<char> open;
    bool balanced = true;

    for (int i = 0; i < text.size(); i++) {
        char c = text[i];
        if (c == '(' || c == '[' || c == '{') {
            open.push(c);
        } else {
            if (open.empty()) {
                balanced = false;
                break;
            }
            open.pop();
        }
    }

    cout << (balanced && open.empty() ? "balanced" : "not balanced") << endl;
    return 0;
}