#include <stdio.h>
#include <string.h>

int match(char open, char close) {
    return (open == '{' && close == '}') || (open == '[' && close == ']') ||
           (open == '(' && close == ')'); 
}

void check_brackets(const char *code) {
    char stack[100];
    int top = -1;

    printf("Read: %s", code);

    for (int i = 0; code[i] != '\0'; i++) {
        char c = code[i];
        if (c == '{' || c == '[' || c == '(') {
            stack[++top] = c;
        } else if (c == '}' || c == ']' || c == ')') {
            if (top == -1) {
                printf("Unexpected closing bracket %c at position %d\n", c, i);
                return;
            }
            if (!match(stack[top], c)) {
                printf("Crossed bracket %c in %d, expected %c\n", c, i, stack[top]);
                return;
            }
            top--;
        }
    }
    if (top == -1) {
        printf("All brackets OK\n");
    } else {
        printf("Unmatched opening bracket %c\n", stack[top]);
    }
}

int main() {
    char code[100];
    fgets(code, 100, stdin);
    check_brackets(code);
    return 0;
}