Breaking News: Grepper is joining You.com. Read the official announcement!

All Vectors Are Not Created Equal

Bishoy Botros answered on June 27, 2022 Popularity 1/10 Helpfulness 1/10

answer All Vectors Are Not Created Equal

All Vectors Are Not Created Equal

Comment

#include <bits/stdc++.h>

using namespace std;
#define Ma7moud_7amdy ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
#define Open_Sesame Open()
#define watch(x) cout << #x << " = " << x << endl;
#define endl "\n"
typedef long long ll;

void Open() {
#ifndef ONLINE_JUDGE
    freopen("standard.in", "r", stdin);
    freopen("standard.out", "w", stdout);
#endif
}

const int mod = ll(1e9 + 7), N = 2e5 + 5;

//"The secret of getting ahead is getting started". Mark Twain
int test_td;
map<ll, ll> mp;


ll get_ans_plz(vector<int> &v) {
    ll ans = 0, sum = v[0];
    for (int i = 1; i < v.size(); ++i) {
        ans += 1LL * v[i] * i + sum;
        sum += v[i];
    }
    return ans;
}

ll get_ans_plz(vector<int> &v, vector<int> &v2) {
    if (v.empty() || v2.empty())return 0;
    sort(v2.begin(), v2.end());
    vector<ll> pre(v2.size());
    pre[0] = v2[0];
    for (int i = 1; i < v2.size(); ++i) {
        pre[i] = pre[i - 1] + v2[i];
    }
    ll ans = 0;
    for (int i = 0; i < v.size(); ++i) {
        int idx = upper_bound(v2.begin(), v2.end(), v[i]) - v2.begin();
        ll sum_previous = 0;
        ll cnt_prv = 0, cnt_nxt = 0;
        ll sum_next = 0;
        if (idx == v2.size()) {
            sum_previous = pre.back();
            cnt_prv = v2.size();
        } else if (idx == 0) {
            sum_next = pre.back();
            cnt_nxt = v2.size();
        } else {
            sum_previous = pre[idx-1];
            cnt_prv = idx;
            cnt_nxt = (int)v2.size() - cnt_prv;
            sum_next = pre.back() - pre[idx-1];
        }

        ans += cnt_prv * v[i] - sum_previous;
        ans += sum_next - cnt_nxt * v[i];
    }
    return ans;
}

void solve() {
    int n;
    cin >> n;
    vector<pair<int, int>> v(n);
    vector<int> pos1, neg1, pos2, neg2;
    for (int i = 0; i < n; ++i) {
        cin >> v[i].first >> v[i].second;
        if (v[i].first < 0)neg1.push_back(-v[i].first);
        else pos1.push_back(v[i].first);

        if (v[i].second < 0)neg2.push_back(-v[i].second);
        else pos2.push_back(v[i].second);
    }
    ll ans = 0;
    ans += get_ans_plz(pos1);
    ans += get_ans_plz(neg1);
    ans += get_ans_plz(pos2);
    ans += get_ans_plz(neg2);

    ans += get_ans_plz(pos1, neg1);
    ans += get_ans_plz(pos2, neg2);
    cout << ans << endl;

}

int main() {
    Ma7moud_7amdy;
    Open_Sesame;
    int t = 1;
    // cin >> t;
    while (test_td++ < t)
        solve();

}
//"There's a way to do it better - find it". Thomas A. Edison

Popularity 1/10 Helpfulness 1/10 Language whatever

Source: codeforces.com

Tags: whatever

Link to this answer
Share Copy Link

Contributed on Jun 27 2022

Bishoy Botros

0 Answers Avg Quality 2/10

All Vectors Are Not Created Equal

Contents

More Related Answers

All Vectors Are Not Created Equal

Grepper

Documentation

Social

Legal

Contact

Oops, You will need to install Grepper and log-in to perform this action.