Submission #988930

#	Time	Username	Problem	Language	Result	Execution time	Memory
988930		LOLOLO	Swap Swap Sort (CCO21_day1problem1)	C++17	25 / 25	1769 ms	85332 KiB

Main

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
 
#define           f     first
#define           s     second
#define           pb    push_back
#define           ep    emplace
#define           eb    emplace_back
#define           lb    lower_bound
#define           ub    upper_bound
#define       all(x)    x.begin(), x.end()
#define      rall(x)    x.rbegin(), x.rend()
#define   uniquev(v)    sort(all(v)), (v).resize(unique(all(v)) - (v).begin())
#define     mem(f,x)    memset(f , x , sizeof(f))
#define        sz(x)    (ll)(x).size()
#define  __lcm(a, b)    (1ll * ((a) / __gcd((a), (b))) * (b))
#define          mxx    *max_element
#define          mnn    *min_element
#define    cntbit(x)    __builtin_popcountll(x)
#define       len(x)    (int)(x.length())
 
const int N = 1e5 + 10;
struct fen{
    vector <int> f;
    int N;
    void ass(int n) {
        N = n;
        f.assign(n + 1, 0);
    }

    void upd(int i, int x) {
        for (; i; i -= i & (-i))
            f[i] += x;
    }

    int get(int i) {
        int s = 0;
        for (; i <= N; i += i & (-i))
            s += f[i];

        return s;
    }
};

vector <int> pos[N];
int perm[N];
map <pair <int, int>, ll> mp;

ll cal(int x, int y) {
    if (sz(pos[x]) > sz(pos[y]))
        return sz(pos[x]) * sz(pos[y]) - cal(y, x);

    if (mp.find({x, y}) != mp.end())
        return mp[{x, y}];

    ll ans = 0;
    for (auto t : pos[x]) {
        int p = lower_bound(all(pos[y]), t) - pos[y].begin();
        ans += p;
    }

    return mp[{x, y}] = ans;
}

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    int n, k, q;
    cin >> n >> k >> q;

    fen f;
    f.ass(k + 1);

    ll num = 0;
    for (int i = 1; i <= n; i++) {
        int x;
        cin >> x;
        pos[x].pb(i);
        num += f.get(x + 1);
        f.upd(x, 1);
    }

    for (int i = 1; i <= k; i++)
        perm[i] = i;

    for (int i = 0; i < q; i++) {
        int x;
        cin >> x;
        ll tot = sz(pos[perm[x]]) * sz(pos[perm[x + 1]]);
        ll t = cal(perm[x], perm[x + 1]);
        swap(perm[x], perm[x + 1]);
        num += (tot - t - t);
        cout << num << '\n';
    }

    return 0;
} 

/*
5 4 3
1 4 2 1 2
3
2
1
*/

• Subtask 1: 3 / 3
• Subtask 2: 3 / 3
• Subtask 3: 5 / 5
• Subtask 4: 14 / 14