Submission #688110

#	Time	Username	Problem	Language	Result	Execution time	Memory
688110		ksjsjsjsjsjsjs	Homework (CEOI22_homework)	C++14	100 / 100	209 ms	155076 KiB

Main

#include <bits/stdc++.h>
using namespace std;
#define st first
#define nd second
#define lb lower_bound
#define ub upper_bound
#define pb push_back
#define pf push_front
#define _pb pop_back
#define _pf pop_front
#define bg begin
#define ed end
#define ft front
#define bk back
#define ins insert
#define ers erase
#define sz(x) (int)(x).size()
#define all(x) (x).bg(), (x).ed()
#define mtp make_tuple
#define ll long long
#define ull unsigned long long
#define db double
#define ldb long double
#define str string
#define pi pair<int, int>
#define pll pair<ll, ll>
#define vi vector<int>
#define vll vector<ll>
#define vpi vector<pi>
#define vpll vector<pll>
#define FOR(i, l, r) for (int i = (l); i <= (r); ++i)
#define FOS(i, r, l) for (int i = (r); i >= (l); --i)
#define FRN(i, n) for (int i = 0; i < (n); ++i)
#define FSN(i, n) for (int i = (n) - 1; i >= 0; --i)
#define EACH(i, x) for (auto &i : (x))
#define WHILE while
template<typename T> T gcd(T a, T b) { WHILE(b) { a %= b; swap(a, b); } return b; }
template<typename T> T lcm(T a, T b) { return a / gcd(a, b) * b; }
#define file "TEST"
mt19937 rd(chrono::steady_clock::now().time_since_epoch().count());
ll rand(ll l, ll r) { return uniform_int_distribution<ll>(l, r)(rd); }
const int N = 2e6 + 5;
int n = 0, mm[N], s1[N];
str s;
vi adj[N];
bool valid(char c) { return (c >= 'a' && c <= 'z') || c == '?'; }
pi dfs(int u) {
    pi ans = {1, 1};
    if (!adj[u].empty()) {
        pi left = dfs(adj[u][0]), right = dfs(adj[u][1]);
        s1[u] = s1[adj[u][0]] + s1[adj[u][1]];
        if (mm[u] < 0) ans = {min(left.st, right.st), left.nd + right.nd - 1};
        else ans = {left.st + right.st, max(left.nd + s1[adj[u][1]], s1[adj[u][0]] + right.nd)};
    }
    else s1[u] = 1;
//    cerr << u << " : " << ans.st << ' ' << ans.nd << '\n';
    return ans;
}
signed main() {
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
//    freopen(file".inp", "r", stdin);
//    freopen(file".out", "w", stdout);
    cin >> s;
    stack<int> s1;
    FRN(i, sz(s)) {
        if (!valid(s[i])) continue;
        int j = i;
        WHILE(j < sz(s) && valid(s[j])) ++j;
        --j;
        ++n;
        if (!s1.empty()) {
            adj[s1.top()].pb(n);
            if (sz(adj[s1.top()]) == 2) s1.pop();
        }
        if (i == j) continue;
        if (s[i + 1] == 'a') mm[n] = 1;
        else mm[n] = -1;
        s1.push(n);
        i = j;
    }
//        cerr << i << " : ";
//        EACH(j, adj[i]) cerr << j << ' ';
//        cerr << '\n';
//    }
//    cerr << '\n';
    pi tmp = dfs(1);
    cout << tmp.nd - tmp.st + 1;
//    cerr << "\nTime: " << setprecision(5) << fixed << (ldb)clock() / CLOCKS_PER_SEC << "ms\n";
    return 0;
}

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