#include <iostream> #include <stack> #include <string> using namespace std; int main() { string s; getline(cin, s); stack<char> stk; bool valid = true; for (char c : s) { if (c == '(' || c == '[') { stk.push(c); } else if (c == ')' || c == ']') { if (stk.empty()) { valid = false; break; } char top = stk.top(); if ((c == ')' && top == '(') || (c == ']' && top == '[')) { stk.pop(); } else { valid = false; break; } } } if (valid && stk.empty()) { cout << "OK" << endl; } else { cout << "Wrong" << endl; } return 0; }