#include <stdio.h>
#define MAX_SIZE 100

char stack[MAX_SIZE];
int top = -1;

void push(char c) {
    if (top < MAX_SIZE - 1) {
        stack[++top] = c;
    }
}

char pop() {
    if (top >= 0) {
        return stack[top--];
    }
    return '\0';
}

int is_matching_pair(char opening, char closing) {
    return (opening == '(' && closing == ')') ||
           (opening == '[' && closing == ']') ||
           (opening == '{' && closing == '}');
}

int are_parentheses_balanced(char expr[]) {
    int i;
    for (i = 0; expr[i] != '\0'; i++) {
        if (expr[i] == '(' || expr[i] == '[' || expr[i] == '{') {
            push(expr[i]);
        } else if (expr[i] == ')' || expr[i] == ']' || expr[i] == '}') {
            if (top == -1 || !is_matching_pair(pop(), expr[i])) {
                return 0;
            }
        }
    }
    return (top == -1);

int main() {
    char expr[MAX_SIZE];
    printf("Enter an expression: ");
    scanf("%s", expr);

    if (are_parentheses_balanced(expr)) {
        printf("Parentheses are balanced\n");
    } else {
        printf("Parentheses are not balanced\n");
    }

    return 0;
}