Submission #1006360

#	Time	Username	Problem	Language	Result	Execution time	Memory
1006360		aykhn	Homework (CEOI22_homework)	C++17	100 / 100	153 ms	181572 KiB

Main

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

#define inf 0x3F3F3F3F

const int MXN = 5e6 + 5;

int n, r, cnt;
string s;
int adj[MXN][2];
array<int, 2> dp[MXN];
int sz[MXN];
int t[MXN];
vector<int> R; 

array<int, 2> MERGE(array<int, 2> x, array<int, 2> y)
{
  return {min(x[0], y[0]), max(x[1], y[1])};
}

void dfs(int a)
{
  if (t[a] == 2)
  {
    dp[a] = {1, 1};
    sz[a] = 1;
    return;
  }
  dfs(adj[a][0]), dfs(adj[a][1]);
  if (t[a] == 1)
  {
    dp[a] = MERGE({dp[adj[a][0]][0] + dp[adj[a][1]][0], dp[adj[a][0]][1] + sz[adj[a][1]]}, {dp[adj[a][1]][0] + dp[adj[a][0]][0], dp[adj[a][1]][1] + sz[adj[a][0]]});
  }
  else
  {
    dp[a] = MERGE({dp[adj[a][0]][0], dp[adj[a][0]][1] + dp[adj[a][1]][1] - 1}, {dp[adj[a][1]][0], dp[adj[a][1]][1] + dp[adj[a][0]][1] - 1});
  }
  sz[a] = sz[adj[a][0]] + sz[adj[a][1]];
}

signed main()
{
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cin >> s;
  n = s.length();
  string nw;
  for (int i = 0; i < s.length(); i++)
  {
    if (s[i] == ',') continue;
    if (s[i] == '?')
    {
      t[nw.size()] = 2;
      nw.push_back('(');
      nw.push_back(')');
    }
    else if (s[i] == '(' || s[i] == ')') nw.push_back(s[i]);
    else 
    {
      if (s[i + 1] == 'i') t[nw.size()] = 0;
      else t[nw.size()] = 1;
      i += 2;
    }
  }
  vector<int> v;
  R.assign(nw.size(), 0);
  for (int i = (int)nw.size() - 1; i >= 0; i--)
  {
    if (nw[i] == ')') v.push_back(i);
    else R[i] = v.back(), v.pop_back();
  }
  v.clear();
  for (int i = (int)nw.size() - 1; i >= 0; i--)
  {
    if (nw[i] == '(') 
    {
      vector<int> tmp;
      while (!v.empty() && v.back() <= R[i]) tmp.push_back(v.back()), v.pop_back();
      assert(tmp.size() == 2 || tmp.empty());
      v.push_back(i);
      if (tmp.size() == 2) 
      {
        adj[i][0] = tmp[0], adj[i][1] = tmp[1];
      }
    }
  }
  assert(v.size() == 1);
  dfs(v[0]);
  cout << dp[v[0]][1] - dp[v[0]][0] + 1 << '\n';
}

Compilation message (stderr)

Main.cpp: In function 'int main()':
Main.cpp:49:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   49 |   for (int i = 0; i < s.length(); i++)
      |                   ~~^~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 13 / 13
• Subtask 3: 13 / 13
• Subtask 4: 30 / 30
• Subtask 5: 34 / 34