// Arti1990, II UWr
#include <bits/stdc++.h>
#define forr(i, n) for(int i=0; i<n; i++)
#define FOREACH(iter, coll) for(auto iter = coll.begin(); iter != coll.end(); ++iter)
#define FOREACHR(iter, coll) for(auto iter = coll.rbegin(); iter != coll.rend(); ++iter)
#define lbound(P,K,FUN) ({auto SSS=P, PPP = P-1, KKK=(K)+1; while(PPP+1!=KKK) {SSS = (PPP+(KKK-PPP)/2); if(FUN(SSS)) KKK = SSS; else PPP = SSS;} PPP;})
#define testy() int _tests; cin>>_tests; FOR(_test, 1, _tests)
#define CLEAR(tab) memset(tab, 0, sizeof(tab))
#define CONTAIN(el, coll) (coll.find(el) != coll.end())
#define FOR(i, a, b) for(int i=a; i<=b; i++)
#define FORD(i, a, b) for(int i=a; i>=b; i--)
#define MP make_pair
#define PB push_back
#define ff first
#define ss second
#define deb(X) X;
#define SIZE(coll) ((int)coll.size())
#define M 1000000007
#define INF 1000000007LL
using namespace std;
int n, S;
int d[4400007];
struct polka
{
int p, k;
vector <pair<int, int>> l;
set <int> s;
};
polka tab[1000007];
pair <long long, long long> euklid(long long a, long long b)
{
if(b == 0) return make_pair(1, 0);
pair <long long, long long> p = euklid(b, a%b);
return make_pair(p.second, p.first - p.second * (a/b));
}
long long odwr(long long a, long long mod)
{
long long e = euklid(a, mod).first;
return (e < 0 ? mod-((-e) % mod) : (e % mod));
}
int znajdz_max(int nr)
{
int res = 0;
nr += S;
while(nr > 0)
{
res = max(res, d[nr]);
nr /= 2;
}
return res;
}
void wkladaj(int nr, int pocz, int kon, int p, int k, int ile)
{
if(p == pocz && k == kon)
{
d[nr] = ile;
}
else
{
int s = (pocz + kon)/2;
if(k <= s)
wkladaj(nr*2, pocz, s, p, k, ile);
else if(p > s)
wkladaj(nr*2+1, s+1, kon, p, k, ile);
else
{
wkladaj(nr*2, pocz, s, p, s, ile);
wkladaj(nr*2+1, s+1, kon, s+1, k, ile);
}
}
}
int solve()
{
cin >> n;
S = 1;
while(S < 2*n+3)
S *= 2;
FOR(i, 1, n)
{
cin >> tab[i].p >> tab[i].k;
int nr = znajdz_max(tab[i].p);
tab[nr].l.PB({tab[i].p, i});
//cout << "krawedz z " << nr << " do " << i << '\n';
nr = znajdz_max(tab[i].k);
tab[nr].l.PB({tab[i].k, i});
//cout << "krawedz z " << nr << " do " << i << '\n';
wkladaj(1, 0, S-1, tab[i].p, tab[i].k, i);
}
long long res = 0;
FORD(i, n, 1)
{
tab[i].s.insert(i);
for(auto p : tab[i].l)
for(auto el : tab[p.ss].s)
tab[i].s.insert(el);
//cout << "dodaje 1/" << tab[i].s.size() << '\n';
res = (res + odwr(tab[i].s.size(), M))%M;
}
cout << res << '\n';
return 0;
}
int main()
{
std::ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
solve();
return 0;
}
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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 | // Arti1990, II UWr #include <bits/stdc++.h> #define forr(i, n) for(int i=0; i<n; i++) #define FOREACH(iter, coll) for(auto iter = coll.begin(); iter != coll.end(); ++iter) #define FOREACHR(iter, coll) for(auto iter = coll.rbegin(); iter != coll.rend(); ++iter) #define lbound(P,K,FUN) ({auto SSS=P, PPP = P-1, KKK=(K)+1; while(PPP+1!=KKK) {SSS = (PPP+(KKK-PPP)/2); if(FUN(SSS)) KKK = SSS; else PPP = SSS;} PPP;}) #define testy() int _tests; cin>>_tests; FOR(_test, 1, _tests) #define CLEAR(tab) memset(tab, 0, sizeof(tab)) #define CONTAIN(el, coll) (coll.find(el) != coll.end()) #define FOR(i, a, b) for(int i=a; i<=b; i++) #define FORD(i, a, b) for(int i=a; i>=b; i--) #define MP make_pair #define PB push_back #define ff first #define ss second #define deb(X) X; #define SIZE(coll) ((int)coll.size()) #define M 1000000007 #define INF 1000000007LL using namespace std; int n, S; int d[4400007]; struct polka { int p, k; vector <pair<int, int>> l; set <int> s; }; polka tab[1000007]; pair <long long, long long> euklid(long long a, long long b) { if(b == 0) return make_pair(1, 0); pair <long long, long long> p = euklid(b, a%b); return make_pair(p.second, p.first - p.second * (a/b)); } long long odwr(long long a, long long mod) { long long e = euklid(a, mod).first; return (e < 0 ? mod-((-e) % mod) : (e % mod)); } int znajdz_max(int nr) { int res = 0; nr += S; while(nr > 0) { res = max(res, d[nr]); nr /= 2; } return res; } void wkladaj(int nr, int pocz, int kon, int p, int k, int ile) { if(p == pocz && k == kon) { d[nr] = ile; } else { int s = (pocz + kon)/2; if(k <= s) wkladaj(nr*2, pocz, s, p, k, ile); else if(p > s) wkladaj(nr*2+1, s+1, kon, p, k, ile); else { wkladaj(nr*2, pocz, s, p, s, ile); wkladaj(nr*2+1, s+1, kon, s+1, k, ile); } } } int solve() { cin >> n; S = 1; while(S < 2*n+3) S *= 2; FOR(i, 1, n) { cin >> tab[i].p >> tab[i].k; int nr = znajdz_max(tab[i].p); tab[nr].l.PB({tab[i].p, i}); //cout << "krawedz z " << nr << " do " << i << '\n'; nr = znajdz_max(tab[i].k); tab[nr].l.PB({tab[i].k, i}); //cout << "krawedz z " << nr << " do " << i << '\n'; wkladaj(1, 0, S-1, tab[i].p, tab[i].k, i); } long long res = 0; FORD(i, n, 1) { tab[i].s.insert(i); for(auto p : tab[i].l) for(auto el : tab[p.ss].s) tab[i].s.insert(el); //cout << "dodaje 1/" << tab[i].s.size() << '\n'; res = (res + odwr(tab[i].s.size(), M))%M; } cout << res << '\n'; return 0; } int main() { std::ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0); solve(); return 0; } |
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