Submission #549644

#	Time	Username	Problem	Language	Result	Execution time	Memory
549644		minhcool	Diversity (CEOI21_diversity)	C++17	100 / 100	1272 ms	10232 KiB

diversity

#include<bits/stdc++.h>
using namespace std;
 
#define int long long
#define fi first
#define se second
#define pb push_back
 
typedef pair<int, int> ii;
typedef pair<ii, int> iii;
typedef pair<ii, ii> iiii;
 
const int N = 4e5 + 5;
 
const int oo = 1e18 + 7, mod = 1e9 + 7;
 
int n, q, a[N];
 
int cnt[N];
 
int cntt[N];
 
int S = 500;
 
bool cmp(iii a, iii b){
    if(a.fi.fi / S != b.fi.fi / S) return (a.fi.fi / S < b.fi.fi / S);
    else{
        if(!((a.fi.fi / S) & 1)) return (a.fi.se < b.fi.se);
        else return (a.fi.se > b.fi.se);
    }
}
 
vector<iii> queries;
vector<int> big;
set<int> se;
 
void ins(int pos){
    cntt[cnt[a[pos]]]--;
    cnt[a[pos]]++;
    //cout << a[pos] << " " << cnt[a[pos]] << "\n";
    cntt[cnt[a[pos]]]++;
}
 
void er(int pos){
    cntt[cnt[a[pos]]]--;
    cnt[a[pos]]--;
    //cout << a[pos] << " " << cnt[a[pos]] << "\n";
    cntt[cnt[a[pos]]]++;
}
 
int answer[N];
 
void process(){
    cin >> n >> q;
    for(int i = 1; i <= n; i++){
        cin >> a[i];
        cnt[a[i]]++;
        //cnt[a[i]].fi++;
    }
    for(int i = 1; i <= 300000; i++) if(cnt[i] >= S) big.pb(i);
    for(int i = 1; i <= 300000; i++) cnt[i] = 0;
    for(int i = 1; i <= q; i++){
        int l, r;
        cin >> l >> r;
        queries.pb({{l, r}, i});
    }   
    sort(queries.begin(), queries.end(), cmp);
    int lstl = 0, lstr = 0;
    bool ck = 1;
    for(int i = 0; i < q; i++){
        //sort(cnt + 1, cnt + 300000 + 1, greater<ii>());
        while(lstr < queries[i].fi.se){
            //ins(a[lstr]);
            lstr++;
            ins(lstr);
        }
        while(lstl > queries[i].fi.fi){
            lstl--;
            ins(lstl);
        }
        while(lstl < queries[i].fi.fi){
            if(lstl) er(lstl);
            lstl++;
        }
        while(lstr > queries[i].fi.se){
            er(lstr);
            lstr--;
        }
        if(!ck) continue;
        //cout << lstl << " " << lstr << "\n";
        vector<ii> vc1, vc2;
        int total = 0;
        for(int it = 1; it < S; it++){
            if(!cntt[it]) continue;
            int temp1 = (cntt[it] + 1) / 2, temp2 = cntt[it] / 2;
            if(!(total & 1)){
                if(temp1) vc1.pb({it, temp1});
                if(temp2) vc2.pb({it, temp2});
            }
            else{
                if(temp2) vc1.pb({it, temp2});
                if(temp1) vc2.pb({it, temp1});
            }
            total += cntt[it];
        }
        set<int> uos;
        for(auto it : big){
            if(cnt[it] < S) continue;
            //if(uos.find(cnt[it]) != uos.end()) continue;
            uos.insert(cnt[it]);
        }
        for(auto it : uos){
            int temp1 = (cntt[it] + 1) / 2, temp2 = cntt[it] / 2;
            if(!(total & 1)){
                if(temp1) vc1.pb({it, temp1});
                if(temp2) vc2.pb({it, temp2});
            }
            else{
                if(temp2) vc1.pb({it, temp2});
                if(temp1) vc2.pb({it, temp1});
            }
            total += cntt[it];
		}
        //sort(vc1.begin(), vc1.end()), sort(vc2.begin(), vc2.end());
        //for(int j = 1; j <= 5; j++) cout << j << " " << cnt[j] << "\n";
        for(int j = vc2.size() - 1; j >= 0; j--) vc1.pb(vc2[j]);
        //for(auto it : vc1) if(lstl == 1 && lstr == 8) cout << it.fi << " " << it.se << "\n";
        int tol = 0, tol2 = 0, toll = 1;
        for(auto it : vc1){
            //cout << lstl << " " << lstr << " " << it.fi << " " << it.se << "\n";
            int temp = ((it.se * (it.se + 1) * (2 * it.se + 1)) / 6 + (it.se * (it.se + 1)) / 2) / 2 - it.se;
            temp = temp * it.fi * it.fi + toll * it.fi * it.se;
            temp += it.se * (it.fi * (it.fi - 1) / 2);
            temp += tol * ((it.se * (it.se - 1)) / 2) * it.fi;
            toll += ((it.se * (it.se + 1)) / 2) * it.fi + tol * (it.se - 1);
            tol += it.fi * it.se;
            toll += tol;
            tol2 += temp;
        }
        answer[queries[i].se] = tol2;
        //if(!(i % 1000) && (long double)clock() / (long double)CLOCKS_PER_SEC >= 3.0) ck = 0;
    }
    for(int i = 1; i <= q; i++) cout << answer[i] << "\n";
}
 
signed main(){
    ios_base::sync_with_stdio(0);
    //freopen("diverse.inp", "r", stdin);
    //freopen("diverse.out", "w", stdout);
    process();
}

• Subtask 1: 4 / 4
• Subtask 2: 10 / 10
• Subtask 3: 8 / 8
• Subtask 4: 16 / 16
• Subtask 5: 26 / 26
• Subtask 6: 36 / 36