oj.uz

Submission #140080

# Submission time Handle Problem Language Result Execution time Memory
140080 2019-08-02T02:49:31 Z mlyean00 Growing Vegetable is Fun 3 (JOI19_ho_t3) C++17
20 / 100
 50 ms 508 KB 
#include <bits/stdc++.h>
#ifdef DEBUG
#include "debug.hpp"
#else
#pragma GCC optimize("Ofast")
#define trace(...)
#include <bits/stdc++.h>
#define endl '\n'
#endif

using namespace std;

const string COL = "RGY";

int count_inversions(vector<int>& v, int l, int r) {
    if (r - l == 1) return 0;

    int mid = (l + r) / 2;

    int ans = 0;
    ans += count_inversions(v, l, mid);
    ans += count_inversions(v, mid, r);

    vector<int> m;
    m.reserve(r - l);
    int ptr1 = l, ptr2 = mid;

    while (ptr1 < mid || ptr2 < r) {
        if (ptr1 == mid) {
            m.push_back(v[ptr2++]);
        } else if (ptr2 == r) {
            m.push_back(v[ptr1++]);
            ans += ptr2 - mid;
        } else if (v[ptr1] < v[ptr2]) {
            m.push_back(v[ptr1++]);
            ans += ptr2 - mid;
        } else {
            m.push_back(v[ptr2++]);
        }
    }

    copy(m.begin(), m.end(), v.begin() + l);

    return ans;
}

int count_swaps(string s, string const& t) {
    int n = s.length();
    vector<stack<int>> st(3);
    for (int i = n - 1; i >= 0; --i) {
        st[COL.find(t[i])].push(i);
    }
    vector<int> v(n);
    for (int i = 0; i < n; ++i) {
        int c = COL.find(s[i]);
        if (st[c].empty()) return INT_MAX;
        v[i] = st[c].top();
        st[c].pop();
    }
    return count_inversions(v, 0, n);
}

int subtask_1(int n, string s) {
    int ans = INT_MAX;

    for (int i = 0; i < 3; ++i) {
        for (int j = 0; j < 1 << (n - 1); ++j) {
            string t;
            int prev_c = i;
            t.push_back(COL[prev_c]);
            for (int k = 0; k < n - 1; ++k) {
                int bit = (j >> k) & 1;
                prev_c = (prev_c + bit + 1) % 3;
                t.push_back(COL[prev_c]);
            }
            ans = min(count_swaps(s, t), ans);
        }
    }

    if (ans == INT_MAX) ans = -1;

    return ans;
}

int subtask_3(int n, string s) {
    string t1, t2;
    for (int i = 0; i < n; ++i) {
        t1.push_back("RG"[i % 2]);
        t2.push_back("GR"[i % 2]);
    }
    int ans = min(count_swaps(s, t1), count_swaps(s, t2));

    if (ans == INT_MAX) ans = -1;

    return ans;
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(NULL);

    int n;
    string s;
    cin >> n >> s;

    int ans;
    if (n <= 15) {
        ans = subtask_1(n, s);
    } else {
        ans = subtask_3(n, s);
    }

    cout << ans << endl;

    return 0;
}

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 376 KB Output is correct
3 Correct 2 ms 376 KB Output is correct
4 Correct 3 ms 376 KB Output is correct
5 Correct 45 ms 376 KB Output is correct
6 Correct 48 ms 376 KB Output is correct
7 Correct 44 ms 376 KB Output is correct
8 Correct 48 ms 380 KB Output is correct
9 Correct 40 ms 420 KB Output is correct
10 Correct 43 ms 376 KB Output is correct
11 Correct 45 ms 416 KB Output is correct
12 Correct 50 ms 508 KB Output is correct
13 Correct 44 ms 376 KB Output is correct
14 Correct 20 ms 476 KB Output is correct
15 Correct 43 ms 376 KB Output is correct
16 Correct 42 ms 384 KB Output is correct
17 Correct 20 ms 380 KB Output is correct

Subtask #2
0 / 55.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 376 KB Output is correct
3 Correct 2 ms 376 KB Output is correct
4 Correct 3 ms 376 KB Output is correct
5 Correct 45 ms 376 KB Output is correct
6 Correct 48 ms 376 KB Output is correct
7 Correct 44 ms 376 KB Output is correct
8 Correct 48 ms 380 KB Output is correct
9 Correct 40 ms 420 KB Output is correct
10 Correct 43 ms 376 KB Output is correct
11 Correct 45 ms 416 KB Output is correct
12 Correct 50 ms 508 KB Output is correct
13 Correct 44 ms 376 KB Output is correct
14 Correct 20 ms 476 KB Output is correct
15 Correct 43 ms 376 KB Output is correct
16 Correct 42 ms 384 KB Output is correct
17 Correct 20 ms 380 KB Output is correct
18 Incorrect 2 ms 376 KB Output isn't correct
19 Halted 0 ms 0 KB -

Subtask #3
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 376 KB Output is correct
3 Correct 2 ms 376 KB Output is correct
4 Correct 3 ms 416 KB Output is correct
5 Correct 2 ms 376 KB Output is correct
6 Correct 2 ms 376 KB Output is correct
7 Correct 2 ms 376 KB Output is correct
8 Correct 2 ms 376 KB Output is correct
9 Correct 2 ms 380 KB Output is correct
10 Correct 2 ms 376 KB Output is correct
11 Correct 2 ms 376 KB Output is correct
12 Correct 2 ms 376 KB Output is correct
13 Correct 2 ms 296 KB Output is correct
14 Correct 2 ms 376 KB Output is correct
15 Correct 2 ms 376 KB Output is correct
16 Correct 2 ms 376 KB Output is correct

Subtask #4
0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 376 KB Output is correct
3 Correct 2 ms 376 KB Output is correct
4 Correct 3 ms 376 KB Output is correct
5 Correct 45 ms 376 KB Output is correct
6 Correct 48 ms 376 KB Output is correct
7 Correct 44 ms 376 KB Output is correct
8 Correct 48 ms 380 KB Output is correct
9 Correct 40 ms 420 KB Output is correct
10 Correct 43 ms 376 KB Output is correct
11 Correct 45 ms 416 KB Output is correct
12 Correct 50 ms 508 KB Output is correct
13 Correct 44 ms 376 KB Output is correct
14 Correct 20 ms 476 KB Output is correct
15 Correct 43 ms 376 KB Output is correct
16 Correct 42 ms 384 KB Output is correct
17 Correct 20 ms 380 KB Output is correct
18 Incorrect 2 ms 376 KB Output isn't correct
19 Halted 0 ms 0 KB -