Submission #491817

#	Time	Username	Problem	Language	Result	Execution time	Memory
491817		Victor	Vim (BOI13_vim)	C++17	60 / 100	461 ms	204880 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;

int n, cnt = 0, memo[5001][5001], nxt[5001][130], prev_pos[130], prev_skip_e = 0, skip_e[5001],prefix[5001];
vi e;

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 (e[taken] <= pos) {
        int nxt_taken = prefix[pos];
        int nxt_pos = skip_e[e[taken]];
        // cout << "pos = " << pos << " taken = " << taken << " nxt_taken = " << nxt_taken << " nxt_pos = " << nxt_pos << endl;
        ans = (pos - e[taken]) + dp(nxt_pos, nxt_taken);
    }

    rep(i, 'a', 'k') {
        if (i == 'e') continue;
        int npos = nxt[pos][i];
        if (npos != -1) ans = min(ans, 2 + dp(npos, 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(prev_pos, 0, sizeof(prev_pos));
    memset(prefix, 0, sizeof(prefix));
    memset(memo, -1, sizeof(memo));
    memset(nxt, -1, sizeof(nxt));

    cnt = 0;
    cin >> n >> str;
    rep(i, 0, n) {
        char let = str[i];
        rep(j, prev_pos[let], i) nxt[j][let] = i;

        prev_pos[let] = i;
        if (let != 'e') {
            rep(j,prev_skip_e,i)skip_e[j]=i;
            prev_skip_e = i;
        } else{
            ++cnt;
            e.pb(i);
            ++prefix[i];
        }
        prefix[i+1]=prefix[i];
    }

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

Compilation message (stderr)

vim.cpp: In function 'int main()':
vim.cpp:75:25: warning: array subscript has type 'char' [-Wchar-subscripts]
   75 |         rep(j, prev_pos[let], i) nxt[j][let] = i;
      |                         ^~~
vim.cpp:8:36: note: in definition of macro 'rep'
    8 | #define rep(i, a, b) for (int i = (a); i < (b); ++i)
      |                                    ^
vim.cpp:75:41: warning: array subscript has type 'char' [-Wchar-subscripts]
   75 |         rep(j, prev_pos[let], i) nxt[j][let] = i;
      |                                         ^~~
vim.cpp:77:18: warning: array subscript has type 'char' [-Wchar-subscripts]
   77 |         prev_pos[let] = i;
      |                  ^~~

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