oj.uz

Submission #599827

# Submission time Handle Problem Language Result Execution time Memory
599827 2022-07-20T01:30:36 Z yanndev Boarding Passes (BOI22_passes) C++17
55 / 100
 57 ms 2248 KB 
#include <bits/stdc++.h>
#define int long long
#define lgd long long
using namespace std;

lgd dp[(int)(1 << 15) + 42];
vector<int> vals[16];

signed main() {
    string s;
    cin >> s;
    int n = (int)s.size();
    /*for (int i = 0; i < n; i++)
        s += 'A';*/
    int g = 0;
    vector<char> comp {};

    for (int i = 0; i < n; i++)
        comp.push_back(s[i]);

    sort(comp.begin(), comp.end());
    comp.resize(unique(comp.begin(), comp.end()) - comp.begin());

    for (int i = 0; i < n; i++)
        vals[lower_bound(comp.begin(), comp.end(), s[i]) - comp.begin()].push_back(i);

    g = (int)comp.size();
    //cout << g << '\n';
    dp[0] = 0;

    for (int mask = 1; mask < (1 << g); mask++) {
        dp[mask] = 1e18;

        vector<int> pref (n, 0);
        for (int group = 0; group < g; group++)
            if (mask & (1 << group))
                for (auto& x: vals[group])
                    pref[x]++;
        for (int pos = 1; pos < n; pos++)
            pref[pos] += pref[pos - 1];

        for (int lst = 0; lst < g; lst++) {
            if (mask & (1 << lst)) {
                // put everyone to the left 
                lgd esp = 0;
                for (int id = 0; id < (int)vals[lst].size(); id++) {
                    // inversions bcs of other groups, remove the ones from lst
                    esp += pref[vals[lst][id]] - (id + 1);
                }
                // add expected inversions from lst permutations
                lgd transi = 4 * esp + ((int)vals[lst].size() * ((int)vals[lst].size() - 1));
                
                // fix right limit
                for (int id = (int)vals[lst].size() - 1; id >= 0; id--) {
                    // remove from the left side
                    esp -= pref[vals[lst][id]];
                    esp += (id + 1);

                    // inversions bcs of other groups
                    esp += pref.back() - pref[vals[lst][id]];
                    // remove from lst
                    esp -= (int)vals[lst].size() - (id + 1);
                    transi = min(transi, 4 * esp + (((id) * (id - 1)) + ((int)vals[lst].size() - id) * ((int)vals[lst].size() - (id + 1))));
                }

                dp[mask] = min(dp[mask], dp[mask ^ (1 << lst)] + transi);
            }
        }
    }
    
    cout << setprecision(10) << dp[(1 << g) - 1] / 4. << '\n';
}

Subtask #1
0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 5 ms 1860 KB Output is correct
7 Incorrect 6 ms 2248 KB Output isn't correct
8 Halted 0 ms 0 KB -

Subtask #2
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 1 ms 288 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 0 ms 308 KB Output is correct
8 Correct 1 ms 212 KB Output is correct
9 Correct 1 ms 212 KB Output is correct
10 Correct 0 ms 212 KB Output is correct
11 Correct 1 ms 212 KB Output is correct
12 Correct 1 ms 308 KB Output is correct
13 Correct 1 ms 212 KB Output is correct
14 Correct 0 ms 304 KB Output is correct
15 Correct 1 ms 308 KB Output is correct
16 Correct 1 ms 212 KB Output is correct
17 Correct 1 ms 212 KB Output is correct

Subtask #3
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 1 ms 288 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 0 ms 308 KB Output is correct
8 Correct 1 ms 212 KB Output is correct
9 Correct 1 ms 212 KB Output is correct
10 Correct 0 ms 212 KB Output is correct
11 Correct 1 ms 212 KB Output is correct
12 Correct 1 ms 308 KB Output is correct
13 Correct 1 ms 212 KB Output is correct
14 Correct 0 ms 304 KB Output is correct
15 Correct 1 ms 308 KB Output is correct
16 Correct 1 ms 212 KB Output is correct
17 Correct 1 ms 212 KB Output is correct
18 Correct 1 ms 212 KB Output is correct
19 Correct 0 ms 212 KB Output is correct
20 Correct 1 ms 212 KB Output is correct
21 Correct 0 ms 212 KB Output is correct
22 Correct 1 ms 308 KB Output is correct
23 Correct 1 ms 212 KB Output is correct
24 Correct 1 ms 212 KB Output is correct
25 Correct 0 ms 212 KB Output is correct
26 Correct 1 ms 212 KB Output is correct
27 Correct 1 ms 212 KB Output is correct
28 Correct 1 ms 312 KB Output is correct
29 Correct 1 ms 212 KB Output is correct
30 Correct 1 ms 212 KB Output is correct
31 Correct 0 ms 212 KB Output is correct
32 Correct 1 ms 212 KB Output is correct
33 Correct 1 ms 212 KB Output is correct
34 Correct 0 ms 304 KB Output is correct
35 Correct 1 ms 468 KB Output is correct
36 Correct 2 ms 440 KB Output is correct
37 Correct 54 ms 568 KB Output is correct
38 Correct 53 ms 512 KB Output is correct
39 Correct 52 ms 540 KB Output is correct
40 Correct 54 ms 524 KB Output is correct
41 Correct 57 ms 656 KB Output is correct
42 Correct 56 ms 468 KB Output is correct
43 Correct 54 ms 568 KB Output is correct
44 Correct 53 ms 468 KB Output is correct
45 Correct 54 ms 468 KB Output is correct
46 Correct 54 ms 556 KB Output is correct

Subtask #4
0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 5 ms 1860 KB Output is correct
7 Incorrect 6 ms 2248 KB Output isn't correct
8 Halted 0 ms 0 KB -