oj.uz

Submission #512630

# Submission time Handle Problem Language Result Execution time Memory
512630 2022-01-16T14:42:56 Z phathnv Ekoeko (COCI21_ekoeko) C++11
110 / 110
 22 ms 3336 KB 
#include <bits/stdc++.h>
using namespace std;

struct BIT {
    int n;
    vector<int> d;
    void init(int _n) {
        n = _n;
        d.assign(n + 1, 0);
    }
    void update(int x, int val) {
        for (; x <= n; x += x & -x) {
            d[x] += val;
        }
    }
    int get(int x) {
        int res = 0;
        for (;x > 0; x -= x & -x) {
            res += d[x];
        }
        return res;
    }
} bit;

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    int n;
    string s;
    cin >> n >> s;
    vector<int> pos[26], newPos[26];
    for (int i = 0; i < 2 * n; ++i) {
        pos[s[i] - 'a'].push_back(i + 1);
    }
    vector<array<int, 2>> firstHalf;
    for (int i = 0; i < 26; ++i) {
        for (int j = 0; j < (int) pos[i].size() / 2; ++j) {
            firstHalf.push_back({pos[i][j], i});
        }
    }
    sort(firstHalf.begin(), firstHalf.end());
    for (int i = 0; i < 26; ++i) {
        reverse(pos[i].begin(), pos[i].end());
    }
    bit.init(2 * n);
    long long ans = 0;
    for (int t = 0; t < 2; ++t) {
        for (auto x : firstHalf) {
            int p = pos[x[1]].back();
            //cerr << p << endl;
            pos[x[1]].pop_back();
            ans += bit.get(2 * n + 1 - p);
            bit.update(2 * n + 1 - p, 1);
        }
    }
    cout << ans << '\n';
    return 0;
}

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 204 KB Output is correct
2 Correct 5 ms 1332 KB Output is correct
3 Correct 9 ms 2184 KB Output is correct
4 Correct 15 ms 3032 KB Output is correct

Subtask #2
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 204 KB Output is correct
2 Correct 5 ms 1332 KB Output is correct
3 Correct 9 ms 2184 KB Output is correct
4 Correct 15 ms 3032 KB Output is correct
5 Correct 1 ms 204 KB Output is correct
6 Correct 0 ms 204 KB Output is correct
7 Correct 0 ms 288 KB Output is correct
8 Correct 0 ms 204 KB Output is correct

Subtask #3
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 204 KB Output is correct
2 Correct 5 ms 1332 KB Output is correct
3 Correct 9 ms 2184 KB Output is correct
4 Correct 15 ms 3032 KB Output is correct
5 Correct 0 ms 296 KB Output is correct
6 Correct 18 ms 3216 KB Output is correct
7 Correct 16 ms 3084 KB Output is correct
8 Correct 16 ms 3248 KB Output is correct
9 Correct 18 ms 3120 KB Output is correct
10 Correct 18 ms 3120 KB Output is correct
11 Correct 16 ms 3012 KB Output is correct
12 Correct 16 ms 3104 KB Output is correct
13 Correct 15 ms 3172 KB Output is correct
14 Correct 15 ms 3044 KB Output is correct
15 Correct 16 ms 3052 KB Output is correct

Subtask #4
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 204 KB Output is correct
2 Correct 1 ms 316 KB Output is correct
3 Correct 1 ms 332 KB Output is correct
4 Correct 1 ms 332 KB Output is correct
5 Correct 1 ms 332 KB Output is correct
6 Correct 1 ms 332 KB Output is correct
7 Correct 1 ms 332 KB Output is correct
8 Correct 1 ms 332 KB Output is correct
9 Correct 1 ms 332 KB Output is correct
10 Correct 1 ms 332 KB Output is correct
11 Correct 1 ms 352 KB Output is correct

Subtask #5
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 204 KB Output is correct
2 Correct 5 ms 1332 KB Output is correct
3 Correct 9 ms 2184 KB Output is correct
4 Correct 15 ms 3032 KB Output is correct
5 Correct 1 ms 204 KB Output is correct
6 Correct 0 ms 204 KB Output is correct
7 Correct 0 ms 288 KB Output is correct
8 Correct 0 ms 204 KB Output is correct
9 Correct 0 ms 296 KB Output is correct
10 Correct 18 ms 3216 KB Output is correct
11 Correct 16 ms 3084 KB Output is correct
12 Correct 16 ms 3248 KB Output is correct
13 Correct 18 ms 3120 KB Output is correct
14 Correct 18 ms 3120 KB Output is correct
15 Correct 16 ms 3012 KB Output is correct
16 Correct 16 ms 3104 KB Output is correct
17 Correct 15 ms 3172 KB Output is correct
18 Correct 15 ms 3044 KB Output is correct
19 Correct 16 ms 3052 KB Output is correct
20 Correct 1 ms 204 KB Output is correct
21 Correct 1 ms 316 KB Output is correct
22 Correct 1 ms 332 KB Output is correct
23 Correct 1 ms 332 KB Output is correct
24 Correct 1 ms 332 KB Output is correct
25 Correct 1 ms 332 KB Output is correct
26 Correct 1 ms 332 KB Output is correct
27 Correct 1 ms 332 KB Output is correct
28 Correct 1 ms 332 KB Output is correct
29 Correct 1 ms 332 KB Output is correct
30 Correct 1 ms 352 KB Output is correct
31 Correct 0 ms 308 KB Output is correct
32 Correct 16 ms 3336 KB Output is correct
33 Correct 17 ms 3292 KB Output is correct
34 Correct 18 ms 3216 KB Output is correct
35 Correct 22 ms 3148 KB Output is correct
36 Correct 20 ms 3212 KB Output is correct
37 Correct 16 ms 3256 KB Output is correct
38 Correct 15 ms 3184 KB Output is correct
39 Correct 15 ms 3184 KB Output is correct
40 Correct 15 ms 3056 KB Output is correct
41 Correct 21 ms 3064 KB Output is correct