Submission #1264287

#	Time	Username	Problem	Language	Result	Execution time	Memory
1264287		duyanhloveav	Match (CEOI16_match)	C++20	100 / 100	12 ms	12352 KiB

match

#include <bits/stdc++.h>
using namespace std;

#define MASK(i) (1LL << (i))
#define BIT(x, i) (((x) >> (i)) & 1LL)

using ll = long long;

const int mxn = 9 + 1e5;
const int inf = 0x3f3f3f3f;
const ll lnf = 0x3f3f3f3f3f3f3f3f;

int n, nxt[mxn][26];
char res[mxn];
string s;

void solve(int l, int r) {
  if (l > r) return;
  int p = nxt[r][s[l] - 'a'];
  if (!p) {
    cout << "-1\n";
    exit(0);
  }
  res[l] = '(';
  res[p] = ')';
  solve(l + 1, p - 1);
  solve(p + 1, r);
}

void _27augain(void) {
  cin >> s;
  n = s.size();
  s = '*' + s;
  for (int i = 1; i <= n; ++i) {
    for (int j = 0; j < 26; ++j) { 
      if (s[i] - 'a' == j) {
        nxt[i][j] = i;
      } else {
        nxt[i][j] = nxt[max(0, nxt[i - 1][s[i] - 'a'] - 1)][j];
      }
    }
  }
  solve(1, n);
  for (int i = 1; i <= n; ++i) {
    cout << res[i];
  }
}

int32_t main(void) {
#define task "27augain"
  cin.tie(0)->sync_with_stdio(0);
  for (string iext : {"in", "inp"}) {
    if (fopen((task "." + iext).c_str(), "r")) {
      freopen((task "." + iext).c_str(), "r", stdin);
      freopen(task ".out", "w", stdout);
    }
  }
  int testcase = 1;
  // cin >> testcase;
  while (testcase--) {
    _27augain();
  }
  return 0;
}

Compilation message (stderr)

match.cpp: In function 'int32_t main()':
match.cpp:54:14: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   54 |       freopen((task "." + iext).c_str(), "r", stdin);
      |       ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
match.cpp:55:14: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   55 |       freopen(task ".out", "w", stdout);
      |       ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

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