Submission #990177

#	Time	Username	Problem	Language	Result	Execution time	Memory
990177		LOLOLO	Port Facility (JOI17_port_facility)	C++17	0 / 100	1 ms	2392 KiB

port_facility

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
 
#define           f     first
#define           s     second
#define           pb    push_back
#define           ep    emplace
#define           eb    emplace_back
#define           lb    lower_bound
#define           ub    upper_bound
#define       all(x)    x.begin(), x.end()
#define      rall(x)    x.rbegin(), x.rend()
#define   uniquev(v)    sort(all(v)), (v).resize(unique(all(v)) - (v).begin())
#define     mem(f,x)    memset(f , x , sizeof(f))
#define        sz(x)    (ll)(x).size()
#define  __lcm(a, b)    (1ll * ((a) / __gcd((a), (b))) * (b))
#define          mxx    *max_element
#define          mnn    *min_element
#define    cntbit(x)    __builtin_popcountll(x)
#define       len(x)    (int)(x.length())
 
const int N = 1e6 + 10;
int f[N];
void upd(int i, int x) {
    for (; i < N; i += i & (-i))
        f[i] += x;
}

int get(int i) {
    int s = 0;
    for (; i; i -= i & (-i))
        s += f[i];

    return s;
}

ll solve() {
    vector <pair <int, int>> seg;
    int n;
    cin >> n;

    for (int i = 1; i <= n; i++) {
        int a, b;
        cin >> a >> b;
        seg.pb({a, b});
    }

    sort(all(seg));
    stack <int> st;

    for (int i = n - 1; i >= 0; i--) {
        while (sz(st) && seg[i].s > seg[st.top()].s)
            st.pop();

        if (get(seg[i].s))
            return 0;

        if (sz(st)) {
            int nxt = st.top();
            if (seg[i].s > seg[nxt].f) {
                upd(seg[nxt].f, 1);
                upd(seg[i].s, -1);
            }
        }

        st.push(i);
    }

    set <int> save;
    int cnt = 0;

    for (int i = 0; i < n; i++) {
        auto it = save.lower_bound(seg[i].f);
        if (it == save.end() || *it > seg[i].s) {
            cnt++;
        }

        save.insert(seg[i].s);
    }

    ll ans = 1, mod = 1e9 + 7;

    for (int i = 1; i <= cnt; i++) {
        ans = (ans + ans) % mod;
    }

    return ans;
}

/*
 5
 1 4
 2 10
 3 5
 6 9
 7 8
*/
 
int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
 
    int t = 1;
    //cin >> t;
 
    while (t--) {
        cout << solve() << '\n';
    }
 
    return 0;
} 

• Subtask 1: 0 / 10
• Subtask 2: 0 / 12
• Subtask 3: 0 / 56
• Subtask 4: 0 / 22