Submission #423146

#	Time	Username	Problem	Language	Result	Execution time	Memory
423146		Osama_Alkhodairy	Swap Swap Sort (CCO21_day1problem1)	C++17	25 / 25	2090 ms	53220 KiB

Main

#include <bits/stdc++.h>
using namespace std;
#define finish(x) return cout << x << endl, 0
#define ll long long

const int N = 100001;
const int SQ = 100;

int n, k, q, mp[N], f[N], tree[4 * N];
ll cost[N / SQ][N];
vector <int> a, v[N];

void update(int l, int r, int node, int idx){
    if(r < l || r < idx || l > idx) return;
    if(l == r){
        tree[node]++;
        return;
    }
    int mid = (l + r) / 2;
    update(l, mid, 2 * node, idx);
    update(mid + 1, r, 2 * node + 1, idx);
    tree[node] = tree[2 * node] + tree[2 * node + 1];
}
int query(int l, int r, int node, int s, int e){
    if(r < l || r < s || l > e) return 0;
    if(s <= l && r <= e) return tree[node];
    int mid = (l + r) / 2;
    return query(l, mid, 2 * node, s, e) + query(mid + 1, r, 2 * node + 1, s, e);
}
int calc_small(vector <int> &l, vector <int> &r){
    int ret = 0;
    int pl = 0, pr = 0;
    int cnt = 0;
    while(pl < (int)l.size() || pr < (int)r.size()){
        if(pl == (int)l.size()) pr++;
        else if(pr == (int)r.size()){
            ret += cnt;
            pl++;
        }
        else if(l[pl] < r[pr]){
            ret += cnt;
            pl++;
        }
        else{
            cnt++;
            pr++;
        }
    }
    return ret;
}
ll calc_cost(int x, int y){
    if((int)v[x].size() >= SQ){
        return 1LL * v[x].size() * v[y].size() - cost[mp[x]][y];
    }
    if((int)v[y].size() >= SQ){
        return cost[mp[y]][x];
    }
    return calc_small(v[x], v[y]);
}
int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    memset(mp, -1, sizeof mp);
    cin >> n >> k >> q;
    a.resize(n);
    for(auto &i : a){
        cin >> i;
        i--;
    }
    for(int i = 0 ; i < n ; i++){
        v[a[i]].push_back(i);
    }
    int c = 0;
    for(int i = 0 ; i < k ; i++){
        if((int)v[i].size() >= SQ){
            mp[i] = c++;
            int cnt = 0;
            for(int j = 0 ; j < n ; j++){
                if(a[j] == i) cnt++;
                else cost[mp[i]][a[j]] += cnt;
            }
        }
    }
    for(int i = 0 ; i < k ; i++){
        f[i] = i;
    }
    ll ans = 0;
    for(int i = 0 ; i < n ; i++){
        ans += query(0, k - 1, 1, a[i] + 1, k - 1);
        update(0, k - 1, 1, a[i]);
    }
    for(int i = 0 ; i < q ; i++){
        int j;
        cin >> j;
        j--;
        ans -= calc_cost(f[j], f[j + 1]);
        swap(f[j], f[j + 1]);
        ans += calc_cost(f[j], f[j + 1]);
        cout << ans << "\n";
    }
}

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