Submission #1049176

#	Time	Username	Problem	Language	Result	Execution time	Memory
1049176		PoonYaPat	Diversity (CEOI21_diversity)	C++14	64 / 100	30 ms	5600 KiB

diversity

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

const int mx=300000;
int n,q,have[mx+5],res[mx+5];

ll cal(ll x) {return x*(x+1)/2;}

int main() {
    ios_base::sync_with_stdio(0); cin.tie(0);
    cin>>n>>q;
    assert(q==1);
    for (int i=0; i<n; ++i) {
        int x; cin>>x;
        ++have[x];
    }
    cin>>q>>q;
    vector<int> v;
    for (int i=1; i<=mx; ++i) if (have[i]) v.push_back(have[i]);
    sort(v.begin(),v.end());

    int l=0,r=v.size()-1;
    for (int i=0; i<(int)(v.size()); ++i) {
        if (i%2==0) res[l++]=v[i];
        else res[r--]=v[i];
    }

    ll ans=(v.size())*cal(n);
    int sum=0;
    for (int i=0; i<v.size()-1; ++i) {
        sum+=res[i];
        ans-=cal(sum);
    }
    sum=0;
    for (int i=v.size()-1; i>0; --i) {
        sum+=res[i];
        ans-=cal(sum);
    }
    cout<<ans<<"\n";
}

Compilation message (stderr)

diversity.cpp: In function 'int main()':
diversity.cpp:31:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   31 |     for (int i=0; i<v.size()-1; ++i) {
      |                   ~^~~~~~~~~~~

• Subtask 1: 4 / 4
• Subtask 2: 10 / 10
• Subtask 3: 8 / 8
• Subtask 4: 16 / 16
• Subtask 5: 26 / 26
• Subtask 6: 0 / 36