Submission #996498

#	Time	Username	Problem	Language	Result	Execution time	Memory
996498		berWoW	Untitled (POI11_rot)	C++14	0 / 100	45 ms	65536 KiB

Main

#include <bits/stdc++.h>
using namespace std;

#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
// namespace __gnu_pbds

typedef __gnu_pbds::tree<
int,
__gnu_pbds::null_type,
less<int>,
__gnu_pbds::rb_tree_tag,
__gnu_pbds::tree_order_statistics_node_update>
ordered_set;

#define MAX_N 212345

int n, cnt;
int inv[4 * MAX_N];
ordered_set trunks[4 * MAX_N];

void read_trunk(int u) {
    int p;
    scanf("%d", &p);

    if (p != 0) { trunks[u].insert(p); return; }

    read_trunk(2 * u), read_trunk(2 * u + 1);
}

void count_inv(int u) {
    if (trunks[u].size()) return;

    int l = 2 * u, r = 2 * u + 1;

    count_inv(l), count_inv(r);

    if (trunks[l].size() < trunks[r].size()) trunks[l].swap(trunks[r]);

    int inv_l_r = 0, inv_r_l = 0;

    int i = 0;
    for (auto it = trunks[r].begin(); it != trunks[r].end(); it++) {
        trunks[l].insert(*it);
        int pos = trunks[l].order_of_key(*it);
        inv_l_r += trunks[l].size() - pos - 1;
        inv_r_l += pos - i++;
    }

    inv[u] = inv[l] + inv[r] + min(inv_l_r, inv_r_l);
    trunks[u].swap(trunks[2 * u]);
}

int main() {
    scanf("%d", &n);
    read_trunk(1);
    count_inv(1);
    printf("%d\n", inv[1]);
}

Compilation message (stderr)

rot.cpp: In function 'void read_trunk(int)':
rot.cpp:24:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   24 |     scanf("%d", &p);
      |     ~~~~~^~~~~~~~~~
rot.cpp: In function 'int main()':
rot.cpp:55:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   55 |     scanf("%d", &n);
      |     ~~~~~^~~~~~~~~~

• Subtask 1: 0 / 9
• Subtask 2: 0 / 9
• Subtask 3: 0 / 9
• Subtask 4: 0 / 9
• Subtask 5: 0 / 9
• Subtask 6: 0 / 9
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• Subtask 10: 0 / 9
• Subtask 11: 0 / 10