[Link] https://www.acmicpc.net/problem/7453
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#include <algorithm>
#include <iostream>
#include <vector>
#include <map>
#include <set>
#include <queue>
#include <cstring>
// #include <bits/stdc++.h>
using namespace std;
#define for0(i, n) for(int i = 0; i < n; i++)
#define for1(i, n) for(int i = 1; i < n; i++)
#define fori(s, e) for(int i = s; i < e; i++)
#define ll long long
#define endl "\n"
#define nulls '\0'
#define dkdk " "
const int MAX = 5e5 + 1;
int n;
vector<int> a, b, c, d;
int main() {
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
cin >> n;
a.resize(n);
b.resize(n);
c.resize(n);
d.resize(n);
for0(i, n) cin >> a[i] >> b[i] >> c[i] >> d[i];
sort(a.begin(), a.end());
sort(b.begin(), b.end());
sort(c.begin(), c.end());
sort(d.begin(), d.end());
vector<int> ab, cd;
for0(i, n) {
for0(j, n) {
ab.push_back(a[i] + b[j]);
cd.push_back(c[i] + d[j]);
}
}
sort(ab.begin(), ab.end());
sort(cd.begin(), cd.end());
int ab_idx = 0, cd_idx = cd.size() - 1;
ll cnt = 0;
while(ab_idx < ab.size() && cd_idx >= 0) {
int ab_val = ab[ab_idx], cd_val = cd[cd_idx];
int sum = ab_val + cd_val;
if(sum == 0) {
int abcnt = 1, cdcnt = 1;
while(ab_idx + 1 < ab.size() && ab[ab_idx + 1] == ab_val) { abcnt++; ab_idx++; }
while(cd_idx - 1 >= 0 && cd[cd_idx - 1] == cd_val) { cdcnt++; cd_idx--; }
cnt+=(ll)abcnt * cdcnt;
ab_idx++; cd_idx--;
} else if(sum > 0) cd_idx--;
else ab_idx++;
}
cout << cnt;
return 0;
}