Submission #202300

#	Time	Username	Problem	Language	Result	Execution time	Memory
202300		quocnguyen1012	Match (CEOI16_match)	C++14	100 / 100	21 ms	12148 KiB

match

#include <bits/stdc++.h>

#define fi first
#define se second
#define mp make_pair
#define pb push_back

using namespace std;
typedef long long ll;

const int maxn = 1e5 + 5;

int N;
int last[maxn][26];
string str;
char res[maxn];

void match(int l, int r)
{
  if (l > r) return;
  if (l % 2 == r % 2){
    cout << -1;
    exit(0);
  }
  int mid = last[r][str[l] - 'a'];
  res[l] = '('; res[mid] = ')';
  match(l + 1, mid - 1);
  match(mid + 1, r);
}

signed main(void)
{
  ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
  if (fopen("A.INP", "r")){
    freopen("A.INP", "r", stdin);
    freopen("A.OUT", "w", stdout);
  }
  cin >> str; N = str.size();
  str = " " + str;
  for (int i = 0; i < 26; ++i){
    last[0][i] = 1;
  }
  for (int i = 1; i <= N; ++i){
    for (int j = 0; j < 26; ++j){
      if (str[i] - 'a' == j){
        last[i][j] = i;
      }
      else{
        last[i][j] = last[last[i - 1][str[i] - 'a'] - 1][j];
      }
    }
  }
  match(1, N);
  for (int i = 1; i <= N; ++i){
    cout << res[i];
  }
}

Compilation message (stderr)

match.cpp: In function 'int main()':
match.cpp:35:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
     freopen("A.INP", "r", stdin);
     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~
match.cpp:36:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
     freopen("A.OUT", "w", stdout);
     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~

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