1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
| #include <bits/stdc++.h>
#pragma optimization_level 3
#pragma GCC optimize("Ofast,no-stack-protector,unroll-loops,fast-math,O3")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx")
#pragma GCC optimize("Ofast")
#pragma GCC target("avx,avx2,fma")
#pragma GCC optimization ("unroll-loops")
using namespace std;
struct PairHash {
inline std::size_t operator()(const std::pair<int, int> &v) const { return v.first * 31 + v.second; }
};
#define Code ios_base::sync_with_stdio(false);
#define By ios::sync_with_stdio(0);
#define Sumfi cout.tie(NULL);
using ll = long long;
using ld = long double;
const ld PI = 3.14159265358979323846;
const ll INF = 1e18;
const ld EPS = 1e-9;
const ll MAX_N = 101010;
const ll mod = 998244353;
typedef pair<ll, ll> pll;
typedef vector<pll> vpll;
typedef array<ll,3> all3;
typedef array<ll,5> all5;
typedef vector<all3> vall3;
typedef vector<all5> vall5;
typedef vector<ll> vll;
typedef vector<vll> vvll;
typedef vector<int> vi;
typedef vector<string> vs;
typedef vector<vs> vvs;
typedef unordered_set<ll> usll;
typedef unordered_set<pll, PairHash> uspll;
typedef unordered_map<ll, ll> umll;
#define rep(i,n) for(ll i=0;i<n;i++)
#define rrep(i,m,n) for(ll i=n;i>=m;i--)
#define all(a) begin(a), end(a)
#define rall(a) rbegin(a), rend(a)
ll __gcd(ll x, ll y) { return !y ? x : __gcd(y, x % y); }
ll __lcm(ll x, ll y) { return x * y / __gcd(x,y); }
using namespace std;
ll helper(vll& A, vll& B) {
ll n = A.size(), m = B.size(), i = 0, j = 0, res = 0, c = 0;
while(i < n and j < m) {
if(A[i] == B[j]) {
res += c;
c += 1;
i++,j++;
} else if(A[i] < B[j]) i++;
else j++;
}
return res;
}
ll solve(vpll& A) {
unordered_map<ll, vll> mp;
for(auto& [y, x] : A)
mp[y].push_back(x);
for(auto& [_, v] : mp)
sort(all(v));
ll res = 0;
for(auto it = begin(mp); it != end(mp); it++) {
for(auto iit = next(it); iit != end(mp); iit++) {
res += helper(it->second, iit->second);
}
}
return res;
}
int main() {
Code By Sumfi
ll tc = 1;
for (ll i = 1; i <= tc; i++) {
ll n;
cin>>n;
vpll A(n);
rep(i,n) cin>>A[i].first>>A[i].second;
cout<<solve(A)<<endl;
}
return 0;
}
|
