Submission #758864

#	Time	Username	Problem	Language	Result	Execution time	Memory
758864		lukameladze	허수아비 (JOI14_scarecrows)	C++17	100 / 100	1104 ms	34752 KiB

scarecrows

# include <bits/stdc++.h>
using namespace std;
#define f first
#define s second
// #define int long long
#define pii pair <int, int>
#define pb push_back
const int N = 3e5 + 5;
int t,n;
long long ans;
pii a[N];
map <int, int> mp;
void g(vector <int> v) {
    sort(v.begin(),v.end());
    int cnt = 0;
    for (int i = 0 ; i < v.size(); i++) {
        if (i == 0 || v[i] != v[i - 1]) cnt++, mp[v[i]] = cnt;
    }
}
void comp() {
    vector <int> v;
    for (int i = 1; i <= n; i++) {
        v.pb(a[i].f);
    }
    g(v);
    for (int i = 1; i <= n; i++) {
        a[i].f = mp[a[i].f];
    }
    v.clear();
    for (int i = 1; i <= n; i++) {
        v.pb(a[i].s);
    }
    g(v);
    for (int i = 1; i <= n; i++) {
        a[i].s = mp[a[i].s];
    }
    sort(a + 1, a + n + 1);
}
int tree[N];
void upd(int idx, int val){
    assert(idx != 0);
    for (int i = idx; i < N; i+=i&(-i)) {
        tree[i] += val;
    }
}
int getans(int idx) {
    int pas = 0;
    for (int i = idx; i > 0; i-=i&(-i)) {
        pas += tree[i];
    }
    return pas;
}
void solve(int le, int ri) {
    if (le == ri) return ;
    int mid = (le + ri) / 2;
    set <int> s;
    s.insert(0);
    vector <pii> vecle, vecri;
    for (int i = mid + 1; i <= ri; i++) {
        // patarebshi maximaluri
        auto it = --s.lower_bound(a[i].s);
        int x = (*it);
        if (x + 1 <= a[i].s)
        vecri.pb({x + 1, a[i].s});
        s.insert(a[i].s);
    }
    s.clear();
    s.insert(n + 5);
    for (int i = mid; i >= le; i--) {
        auto it = s.upper_bound(a[i].s);
        int x = (*it);
        if (a[i].s <= (x - 1))
        vecle.pb({a[i].s, x - 1});
        s.insert(a[i].s);
    }
    // ro ikvetebian masetebis raodenoba
    sort(vecle.begin(), vecle.end());
    sort(vecri.begin(), vecri.end());
    /*for (pii sth : vecle) {
        cout<<sth.f<<" "<<sth.s<<"\n";
    }
    for (pii sth : vecri) {
        cout<<sth.f<<"-"<<sth.s<<"\n";
    }
    cout<<"\n";*/
    int id = 0;
    for (pii sth : vecle) {
        while (id < vecri.size() && vecri[id].f <= sth.f) {
            upd(vecri[id].s, 1);
            id++;
        }
        ans += (getans(sth.s) - getans(sth.f - 1));
    }

    for (int i = 0; i < id; i++) {
        upd(vecri[i].s, -1);
    }
    solve(le, mid);
    solve(mid + 1, ri);
}
main() {
	std::ios_base::sync_with_stdio(false),cin.tie(0),cout.tie(0);
	cin>>n;
	for (int i = 1; i <= n; i++) {
        cin>>a[i].f>>a[i].s;
	}
    comp();
    solve(1, n);
    cout<<ans<<"\n";
}

Compilation message (stderr)

scarecrows.cpp: In function 'void g(std::vector<int>)':
scarecrows.cpp:16:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   16 |     for (int i = 0 ; i < v.size(); i++) {
      |                      ~~^~~~~~~~~~
scarecrows.cpp: In function 'void solve(int, int)':
scarecrows.cpp:88:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   88 |         while (id < vecri.size() && vecri[id].f <= sth.f) {
      |                ~~~^~~~~~~~~~~~~~
scarecrows.cpp: At global scope:
scarecrows.cpp:101:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
  101 | main() {
      | ^~~~

• Subtask 1: 5 / 5
• Subtask 2: 10 / 10
• Subtask 3: 85 / 85