Problem p02686 (C++) — buggy submission, verdict: Time Limit Exceeded

// #include <tourist>
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<ll, ll> p;
const int INF = 1e9;
const ll LINF = ll(1e18);
const int MOD = 1000000007;
const int dx[4] = {0, 1, 0, -1}, dy[4] = {-1, 0, 1, 0};
const int Dx[8] = {0, 1, 1, 1, 0, -1, -1, -1},
          Dy[8] = {-1, -1, 0, 1, 1, 1, 0, -1};
#define yes cout << "Yes" << endl
#define YES cout << "YES" << endl
#define no cout << "No" << endl
#define NO cout << "NO" << endl
#define rep(i, n) for (int i = 0; i < n; i++)
#define ALL(v) v.begin(), v.end()
#define debug(v)                                                               \\
  cout << #v << ":";                                                           \\
  for (auto x : v) {                                                           \\
    cout << x << ' ';                                                          \\
  }                                                                            \\
  cout << endl;
template <class T> bool chmax(T &a, const T &b) {
  if (a < b) {
    a = b;
    return 1;
  }
  return 0;
}
template <class T> bool chmin(T &a, const T &b) {
  if (b < a) {
    a = b;
    return 1;
  }
  return 0;
}
// cout<<fixed<<setprecision(15);有効数字15桁
//-std=c++14
//-std=gnu++17
ll gcd(ll a, ll b) { return b ? gcd(b, a % b) : a; }
ll lcm(ll a, ll b) { return a / gcd(a, b) * b; }
ll n;
vector<string> s;
/*
bool compare_by_b(pair<int, int> a, pair<int, int> b)
{
    if (a.second != b.second)
    {
        return a.first < b.first;
    }
    else
    {
        return a.second > b.second;
    }
}
*/
int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  cin >> n;
  for (int i = 0; i < n; i++) {
    string temp;
    cin >> temp;
    s.push_back(temp);
  }
  vector<int> close(n, 0);
  vector<int> open(n, 0);
  rep(i, n) {
    int count = 0;
    rep(j, s[i].size()) {
      if (s[i][j] == ')') {
        if (count) {
          count--;
        } else {
          close[i]++;
        }
      } else {
        count++;
      }
    }
    open[i] = count;
  }
  // debug(open);
  // debug(close);
  vector<pair<int, int>> v;
  int ccount = 0;
  int ocount = 0;
  rep(i, n) {
    if (open[i] == 0)
      ccount += close[i];
    else if (close[i] == 0)
      ocount += open[i];
    else
      v.push_back(make_pair(close[i] - open[i], i));
  }
  sort(ALL(v));
  int count = ocount;
  deque<int> d;
  rep(i, v.size()) {
    while (!d.empty()) {
      int j = d.front();
      if (count >= close[j]) {
        d.pop_front();
        count -= close[j];
        count += open[j];
      } else
        break;
    }
    if (count < close[v[i].second]) {
      d.push_back(v[i].second);
    } else {
      count -= close[v[i].second];
      count += open[v[i].second];
    }
  }
  if (d.empty() && count == ccount)
    yes;
  else
    no;
}


Error: TLE

Fixed submission:

// #include <tourist>
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<ll, ll> p;
const int INF = 1e9;
const ll LINF = ll(1e18);
const int MOD = 1000000007;
const int dx[4] = {0, 1, 0, -1}, dy[4] = {-1, 0, 1, 0};
const int Dx[8] = {0, 1, 1, 1, 0, -1, -1, -1},
          Dy[8] = {-1, -1, 0, 1, 1, 1, 0, -1};
#define yes cout << "Yes" << endl
#define YES cout << "YES" << endl
#define no cout << "No" << endl
#define NO cout << "NO" << endl
#define rep(i, n) for (int i = 0; i < n; i++)
#define ALL(v) v.begin(), v.end()
#define debug(v)                                                               \\
  cout << #v << ":";                                                           \\
  for (auto x : v) {                                                           \\
    cout << x << ' ';                                                          \\
  }                                                                            \\
  cout << endl;
template <class T> bool chmax(T &a, const T &b) {
  if (a < b) {
    a = b;
    return 1;
  }
  return 0;
}
template <class T> bool chmin(T &a, const T &b) {
  if (b < a) {
    a = b;
    return 1;
  }
  return 0;
}
// cout<<fixed<<setprecision(15);有効数字15桁
//-std=c++14
//-std=gnu++17
ll gcd(ll a, ll b) { return b ? gcd(b, a % b) : a; }
ll lcm(ll a, ll b) { return a / gcd(a, b) * b; }
ll n;
vector<string> s;
/*
bool compare_by_b(pair<int, int> a, pair<int, int> b)
{
    if (a.second != b.second)
    {
        return a.first < b.first;
    }
    else
    {
        return a.second > b.second;
    }
}
*/
int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  cin >> n;
  for (int i = 0; i < n; i++) {
    string temp;
    cin >> temp;
    s.push_back(temp);
  }
  vector<int> close(n, 0);
  vector<int> open(n, 0);
  rep(i, n) {
    int count = 0;
    rep(j, s[i].size()) {
      if (s[i][j] == ')') {
        if (count) {
          count--;
        } else {
          close[i]++;
        }
      } else {
        count++;
      }
    }
    open[i] = count;
  }
  // debug(open);
  // debug(close);
  vector<pair<int, int>> v;
  int ccount = 0;
  int ocount = 0;
  rep(i, n) {
    if (open[i] == 0)
      ccount += close[i];
    else if (close[i] == 0)
      ocount += open[i];
    else
      v.push_back(make_pair(close[i] - open[i], i));
  }
  sort(ALL(v));
  int count = ocount;
  deque<int> d;
  rep(i, v.size()) {
    while (!d.empty()) {
      int j = d.front();
      if (count >= close[j]) {
        d.pop_front();
        count -= close[j];
        count += open[j];
      }
    }
    if (count < close[v[i].second]) {
      d.push_back(v[i].second);
    } else {
      count -= close[v[i].second];
      count += open[v[i].second];
    }
  }
  if (d.empty() && count == ccount)
    yes;
  else
    no;
}