Submission #491816

#	Time	Username	Problem	Language	Result	Execution time	Memory
491816		Victor	Vim (BOI13_vim)	C++17	60 / 100	1673 ms	200912 KiB

vim

// #pragma GCC target ("avx,avx2,fma")
// #pragma GCC optimize ("Ofast,inline") // O1 - O2 - O3 - Os - Ofast
// #pragma GCC optimize ("unroll-loops")
#include <bits/stdc++.h>

using namespace std;

#define rep(i, a, b) for (int i = (a); i < (b); ++i)
#define per(i, a, b) for (int i = (b - 1); i >= (a); --i)
#define trav(a, x) for (auto &a : x)

#define all(x) x.begin(), x.end()
#define sz(x) x.size()
#define pb push_back
#define debug(x) cout << #x << " = " << x << endl

#define umap unordered_map
#define uset unordered_set

typedef pair<int, int> ii;
typedef pair<int, ii> iii;
typedef vector<int> vi;
typedef vector<ii> vii;
typedef vector<vi> vvi;

typedef long long ll;
typedef pair<ll, ll> pll;
typedef vector<ll> vll;
typedef vector<pll> vpll;

const int INF = 1'000'000'007;

vi lets[130], skip_e;
int n, cnt = 0, memo[5001][5001];
string str;

int dp(int pos, int taken) {
    if (taken == cnt) return 0;

    int &ans = memo[pos][taken];
    if (ans != -1) return memo[pos][taken];

    ans = INF;
    if (lets['e'][taken] <= pos) {
        int nxt_taken = upper_bound(all(lets['e']), pos) - lets['e'].begin();
        int nxt_pos = *upper_bound(all(skip_e), lets['e'][taken]);
        //cout << "pos = " << pos << " taken = " << taken << " nxt_taken = " << nxt_taken << " nxt_pos = " << nxt_pos << endl;
        ans = (pos - lets['e'][taken]) + dp(nxt_pos, nxt_taken);
    }

    rep(i, 'a', 'k') {
        if (i == 'e') continue;
        vi &vec = lets[i];
        auto it = upper_bound(all(vec), pos);
        if (it != vec.end()) ans = min(ans, 2 + dp(*it, taken));
    }

    //cout << "pos = " << pos << " taken = " << taken << " ans = " << ans << endl;
    return ans;
}

int main() {
    cin.tie(0)->sync_with_stdio(0);
    cin.exceptions(cin.failbit);

    memset(memo, -1, sizeof(memo));

    cin >> n >> str;
    rep(i, 0, n) {
        lets[str[i]].pb(i);
        if (str[i] != 'e') skip_e.pb(i);
    }
    cnt = sz(lets['e']);

    cout << dp(0, 0) + cnt << endl;
    return 0;
}

Compilation message (stderr)

vim.cpp: In function 'int main()':
vim.cpp:70:20: warning: array subscript has type 'char' [-Wchar-subscripts]
   70 |         lets[str[i]].pb(i);
      |                    ^

• Subtask 1: 50 / 50
• Subtask 2: 10 / 10
• Subtask 3: 0 / 40