Submission #861218

#	Time	Username	Problem	Language	Result	Execution time	Memory
861218		vgtcross	Homework (CEOI22_homework)	C++17	53 / 100	96 ms	128208 KiB

Main

#include <bits/stdc++.h>

using namespace std;
using ll = long long;
using pii = pair<int, int>;

const int N = int(1e6) + 1000;

vector<int> ch[N];
int l[N], r[N];
int x[N];

void dfs(int u) {
    if (x[u] == 0) {
        l[u] = r[u] = 0;
        return;
    }
    
    for (int v : ch[u]) dfs(v);
    if (x[u] == 1) {
        l[u] = min(l[ch[u][0]], l[ch[u][1]]);
        r[u] = r[ch[u][0]] + r[ch[u][1]] + 1;
    } else {
        l[u] = l[ch[u][0]] + l[ch[u][1]] + 1;
        r[u] = min(r[ch[u][0]], r[ch[u][1]]);
    }
}

void solve() {
    string s;
    cin >> s;
    
    stack<int> st;
    st.push(0);
    
    int w = 1;
    int i = 0;
    while (i < s.size()) {
        if (s[i] == '?') ch[st.top()].push_back(w++);
        else if (s[i] == 'm') {
            x[w] = s[i+1] == 'a' ? 2 : 1;
            ch[st.top()].push_back(w);
            st.push(w++);
            i += 3;
        } else if (s[i] == ')') st.pop();
        ++i;
    }
    
    dfs(1);
    
    int cnt = 0;
    for (char c : s) cnt += c == '?';
    cout << cnt - l[1] - r[1] << '\n';
}

int main() {
    cin.tie(0) -> sync_with_stdio(0);
    
    solve();
}

Compilation message (stderr)

Main.cpp: In function 'void solve()':
Main.cpp:38:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   38 |     while (i < s.size()) {
      |            ~~^~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 13 / 13
• Subtask 3: 0 / 13
• Subtask 4: 30 / 30
• Subtask 5: 0 / 34