oj.uz

Submission #831089

# Submission time Handle Problem Language Result Execution time Memory
831089 2023-08-19T17:19:25 Z skittles1412 Sorting (IOI15_sorting) C++17
100 / 100
 139 ms 32236 KB 
#include "bits/extc++.h"

using namespace std;

template <typename T, typename... U>
void dbgh(const T& t, const U&... u) {
    cerr << t;
    ((cerr << " | " << u), ...);
    cerr << endl;
}

#ifdef DEBUG
#define dbg(...)                                              \
    cerr << "L" << __LINE__ << " [" << #__VA_ARGS__ << "]: "; \
    dbgh(__VA_ARGS__)
#else
#define dbg(...)
#define cerr   \
    if (false) \
    cerr
#endif

#define endl "\n"
#define long int64_t
#define sz(x) int(std::size(x))

template <typename T>
ostream& operator<<(ostream& out, const vector<T>& arr) {
    out << "[";
    for (int i = 0; i < sz(arr); i++) {
        if (i) {
            out << ", ";
        }
        out << arr[i];
    }
    return out << "]";
}

template <typename A, typename B>
ostream& operator<<(ostream& out, const pair<A, B>& p) {
    return out << "(" << p.first << ", " << p.second << ")";
}

vector<pair<int, int>> min_sort(vector<int> arr) {
    int n = sz(arr);

    vector<int> pos(n);
    for (int i = 0; i < n; i++) {
        pos[arr[i]] = i;
    }
    vector<pair<int, int>> ans;

    auto do_swap = [&](int u, int v) -> void {
        ans.emplace_back(u, v);
        swap(arr[u], arr[v]);
        swap(pos[arr[u]], pos[arr[v]]);
    };

    for (int i = 0; i < n; i++) {
        if (arr[i] == i) {
            continue;
        }
        do_swap(i, pos[i]);
    }

    return ans;
}

bool solve_check(const vector<int>& arr, const vector<pair<int, int>>& swaps) {
    int n = sz(arr);

    vector<int> res(n);

    {
        auto tmp = arr;
        for (auto& [u, v] : swaps) {
            swap(tmp[u], tmp[v]);
        }
        for (int i = 0; i < n; i++) {
            res[tmp[i]] = i;
        }
    }

    auto ans_swaps = min_sort(res);

    if (sz(ans_swaps) > sz(swaps)) {
        return false;
    }
    return true;
}

optional<vector<pair<int, int>>> solve(vector<int> arr,
                                       const vector<pair<int, int>>& swaps) {
    int n = sz(arr);

    vector<int> res(n), pos(n);

    for (int i = 0; i < n; i++) {
        pos[arr[i]] = i;
    }

    {
        auto tmp = arr;
        for (auto& [u, v] : swaps) {
            swap(tmp[u], tmp[v]);
        }
        for (int i = 0; i < n; i++) {
            res[tmp[i]] = i;
        }
    }

    auto ans_swaps = min_sort(res);

    if (sz(ans_swaps) > sz(swaps)) {
        return {};
    }

    vector<pair<int, int>> ans;

    auto do_swap = [&](int u, int v, bool swap_res) -> void {
        swap(arr[u], arr[v]);
        swap(pos[arr[u]], pos[arr[v]]);
        if (swap_res) {
            swap(res[arr[u]], res[arr[v]]);
        }
    };

    for (int t = 0; t < sz(ans_swaps); t++) {
        {
            auto& [u, v] = swaps[t];
            do_swap(u, v, false);
        }
        {
            auto& [u, v] = ans_swaps[t];
            ans.emplace_back(pos[u], pos[v]);
            do_swap(pos[u], pos[v], true);
        }
    }
    for (int t = sz(ans_swaps); t < sz(swaps); t++) {
        ans.emplace_back(0, 0);
    }

    return ans;
}

void grade(vector<int> arr,
           const vector<pair<int, int>>& swaps,
           const vector<pair<int, int>>& ans_swaps) {
    assert(sz(ans_swaps) <= sz(swaps));

    for (int i = 0; i < sz(ans_swaps); i++) {
        if (is_sorted(begin(arr), end(arr))) {
            return;
        }
        {
            auto [u, v] = swaps[i];
            swap(arr[u], arr[v]);
        }
        {
            auto [u, v] = ans_swaps[i];
            swap(arr[u], arr[v]);
        }
    }

    assert(is_sorted(begin(arr), end(arr)));
}

int findSwapPairs(int n,
                  int p_arr[],
                  int m,
                  int swaps_x[],
                  int swaps_y[],
                  int out_p[],
                  int out_q[]) {
    vector<int> arr(p_arr, p_arr + n);

    vector<pair<int, int>> swaps(m);
    for (int i = 0; i < m; i++) {
        swaps[i] = {swaps_x[i], swaps_y[i]};
    }

    int l = 0, r = sz(swaps);
    while (l < r) {
        int mid = (l + r) / 2;
        if (solve_check(arr, vector(swaps.begin(), swaps.begin() + mid))) {
            r = mid;
        } else {
            l = mid + 1;
        }
    }
    auto ans = solve(arr, vector(swaps.begin(), swaps.begin() + l)).value();

    for (int i = 0; i < sz(ans); i++) {
        auto& [p, q] = ans[i];
        out_p[i] = p;
        out_q[i] = q;
    }

    // grade(arr, swaps, ans);
    return sz(ans);
}

Subtask #1
8.0 / 8.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Correct 0 ms 212 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 0 ms 212 KB Output is correct

Subtask #2
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Correct 0 ms 212 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 0 ms 212 KB Output is correct
8 Correct 0 ms 212 KB Output is correct
9 Correct 1 ms 212 KB Output is correct
10 Correct 1 ms 340 KB Output is correct
11 Correct 1 ms 340 KB Output is correct
12 Correct 1 ms 340 KB Output is correct

Subtask #3
16.0 / 16.0

# 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 0 ms 340 KB Output is correct
4 Correct 0 ms 340 KB Output is correct
5 Correct 1 ms 340 KB Output is correct
6 Correct 0 ms 212 KB Output is correct

Subtask #4
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Correct 0 ms 212 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 0 ms 212 KB Output is correct
8 Correct 0 ms 212 KB Output is correct
9 Correct 1 ms 212 KB Output is correct
10 Correct 1 ms 340 KB Output is correct
11 Correct 1 ms 340 KB Output is correct
12 Correct 1 ms 340 KB Output is correct
13 Correct 1 ms 212 KB Output is correct
14 Correct 0 ms 212 KB Output is correct
15 Correct 0 ms 340 KB Output is correct
16 Correct 0 ms 340 KB Output is correct
17 Correct 1 ms 340 KB Output is correct
18 Correct 0 ms 212 KB Output is correct
19 Correct 0 ms 212 KB Output is correct
20 Correct 0 ms 212 KB Output is correct
21 Correct 1 ms 596 KB Output is correct
22 Correct 1 ms 596 KB Output is correct
23 Correct 1 ms 596 KB Output is correct
24 Correct 1 ms 596 KB Output is correct
25 Correct 1 ms 596 KB Output is correct
26 Correct 1 ms 596 KB Output is correct
27 Correct 1 ms 596 KB Output is correct

Subtask #5
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 468 KB Output is correct
2 Correct 1 ms 468 KB Output is correct
3 Correct 1 ms 468 KB Output is correct
4 Correct 1 ms 468 KB Output is correct
5 Correct 1 ms 468 KB Output is correct
6 Correct 1 ms 468 KB Output is correct
7 Correct 1 ms 468 KB Output is correct
8 Correct 1 ms 468 KB Output is correct
9 Correct 1 ms 468 KB Output is correct
10 Correct 1 ms 468 KB Output is correct
11 Correct 1 ms 468 KB Output is correct
12 Correct 1 ms 468 KB Output is correct
13 Correct 1 ms 488 KB Output is correct
14 Correct 1 ms 340 KB Output is correct

Subtask #6
26.0 / 26.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 468 KB Output is correct
2 Correct 1 ms 468 KB Output is correct
3 Correct 1 ms 468 KB Output is correct
4 Correct 1 ms 468 KB Output is correct
5 Correct 1 ms 468 KB Output is correct
6 Correct 1 ms 468 KB Output is correct
7 Correct 1 ms 468 KB Output is correct
8 Correct 1 ms 468 KB Output is correct
9 Correct 1 ms 468 KB Output is correct
10 Correct 1 ms 468 KB Output is correct
11 Correct 1 ms 468 KB Output is correct
12 Correct 1 ms 468 KB Output is correct
13 Correct 1 ms 488 KB Output is correct
14 Correct 1 ms 340 KB Output is correct
15 Correct 115 ms 21000 KB Output is correct
16 Correct 128 ms 21444 KB Output is correct
17 Correct 130 ms 22432 KB Output is correct
18 Correct 56 ms 17792 KB Output is correct
19 Correct 92 ms 18668 KB Output is correct
20 Correct 93 ms 18960 KB Output is correct
21 Correct 95 ms 19020 KB Output is correct
22 Correct 111 ms 22852 KB Output is correct
23 Correct 136 ms 31944 KB Output is correct
24 Correct 139 ms 31456 KB Output is correct
25 Correct 139 ms 31352 KB Output is correct
26 Correct 95 ms 27420 KB Output is correct
27 Correct 91 ms 26548 KB Output is correct
28 Correct 130 ms 31148 KB Output is correct
29 Correct 134 ms 30640 KB Output is correct
30 Correct 76 ms 25376 KB Output is correct
31 Correct 134 ms 31132 KB Output is correct
32 Correct 131 ms 30880 KB Output is correct
33 Correct 139 ms 31372 KB Output is correct
34 Correct 135 ms 31384 KB Output is correct
35 Correct 94 ms 26824 KB Output is correct
36 Correct 47 ms 24448 KB Output is correct
37 Correct 137 ms 32236 KB Output is correct
38 Correct 129 ms 31016 KB Output is correct
39 Correct 130 ms 31224 KB Output is correct