Submission #476128

#	Time	Username	Problem	Language	Result	Execution time	Memory
476128		elgamalsalman	Match (CEOI16_match)	C++14	0 / 100	2 ms	332 KiB

match

#include <bits/stdc++.h>

using namespace std;

int n;
string s;

bool validate(int l, int r) {
  //cerr << "// validate(" << l << ", " << r << ")\n";
  if (r < l) return 1;
  int ind = 0;
  for (int i = l + 1; i <= r; i++) {
    if (s[l] == s[i]) ind = i;
  }
  if (!ind) return 0;
  s[l] = '(';
  s[ind] = ')';
  return (validate(l + 1, ind - 1) && validate(ind + 1, r));
}

int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);

  freopen("match.in", "r", stdin);
  freopen("match.out", "w", stdout);
  
  cin >> s;
  n = (int)s.size();
  if (!validate(0, n - 1)) cout << "-1\n";
  else cout << s << '\n';
}

Compilation message (stderr)

match.cpp: In function 'int main()':
match.cpp:25:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   25 |   freopen("match.in", "r", stdin);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
match.cpp:26:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   26 |   freopen("match.out", "w", stdout);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 10
• Subtask 2: 0 / 27
• Subtask 3: 0 / 63