oj.uz

Submission #673971

# Submission time Handle Problem Language Result Execution time Memory
673971 2022-12-22T13:26:01 Z stanislavpolyn Event Hopping (BOI22_events) C++17
70 / 100
 1500 ms 17264 KB 
#include <bits/stdc++.h>

#define fr(i, a, b) for (int i = (a); i <= (b); ++i)
#define rf(i, a, b) for (int i = (a); i >= (b); --i)
#define fe(x, y) for (auto& x : y)

#define fi first
#define se second
#define pb push_back
#define mp make_pair
#define mt make_tuple

#define all(x) (x).begin(), (x).end()
#define sz(x) (int)(x).size()
#define pw(x) (1LL << (x))

using namespace std;

mt19937_64 rng(228);

#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
template <typename T>
using oset = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
#define fbo find_by_order
#define ook order_of_key

template <typename T>
bool umn(T& a, T b) {
    return a > b ? a = b, 1 : 0;
}
template <typename T>
bool umx(T& a, T b) {
    return a < b ? a = b, 1 : 0;
}

using ll = long long;
using ld = long double;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
template <typename T>
using ve = vector<T>;

const int N = 1e5 + 5;

int n, q;
pii a[N];

ve<int> order;

int to[N];
int d[N];
ve<pii> Q[N];
int ans[N];
//bool subtask1 = 1;

pii get(int v) {
    if (to[v] == v) {
        return {v, 0};
    } else {
        pii p = get(to[v]);
        p.se += d[v];
        to[v] = p.fi;
        d[v] = p.se;
        return {p.fi, p.se};
    }
}

bool TL() {
    return (double)clock() / CLOCKS_PER_SEC > 1.4;
}

ve<int> st;

bool have[N];
bool subtask = 1;
bool subtask1;

int go[N][20];

int main() {
#ifdef LOCAL
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
#else
    ios::sync_with_stdio(0);
    cin.tie(0);
#endif

    cin >> n >> q;

//    subtask1 &= n > 5000 || q > 100;

    ve<int> u;
    fr (i, 1, n) {
        cin >> a[i].fi >> a[i].se;
        order.pb(i);
        u.pb(a[i].se);
    }

    sort(all(u));

    {
        sort(all(order), [](int i, int j) {
            return a[i].fi < a[j].fi || (a[i].fi == a[j].fi && a[i].se > a[j].se);
        });

        fe (i, order) {
            if (sz(st) && a[st.back()].se >= a[i].se) {
                to[i] = st.back();
                continue;
            }
            st.pb(i);
            have[i] = 1;
        }


        fr (i, 1, sz(st) - 1) {
            assert(a[st[i]].fi > a[st[i - 1]].fi);
            assert(a[st[i]].se > a[st[i - 1]].se);
        }

        {
            int mx = -1e9;
            int mxI = -1;
            int ptr = 0;

            fe (i, st) {
                while (ptr < sz(st) && a[st[ptr]].fi <= a[i].se) {
                    if (umx(mx, a[st[ptr]].se)) {
                        mxI = st[ptr];
                    }
                    ptr++;
                }

                if (mx >= a[i].se) {
                    to[i] = mxI;
                } else {
                    assert(0);
                    to[i] = -1;
                }
            }
        }

        subtask &= sz(st) == n;
    }

    if (subtask) {
        fr (i, 1, n) {
            go[i][0] = to[i];
        }
        fr (p, 1, 19) {
            fr (i, 1, n) {
                go[i][p] = go[go[i][p - 1]][p - 1];
            }
        }

        fr (i, 1, q) {
            int s, e;
            cin >> s >> e;

            if (s == e) {
                cout << "0\n";
                continue;
            }

            if (a[s].se > a[e].se) {
                cout << "impossible\n";
                continue;
            }

            int v = s;
            int ans = 0;

            rf (p, 19, 0) {
                if (!go[v][p]) continue;

                int nxt = go[v][p];
                if (a[nxt].se < a[e].se) {
                    v = go[v][p];
                    ans += pw(p);
                }
            }

            while (1) {
                if (a[to[v]].se == a[v].se || a[to[v]].se > a[e].se || a[v].se >= a[e].fi) {
                    break;
                }
                v = to[v];
                ans++;
            }

            if (a[v].se >= a[e].fi) {
                ans++;
                cout << ans << "\n";
            } else {
                cout << "impossible\n";
            }

        }


        return 0;
    }

//    fr (i, 1, n) {
//        int p1 = lower_bound(all(u), a[i].fi) - u.begin();
//        int p2 = upper_bound(all(u), a[i].se) - u.begin() - 1;
//        if (max(0, p2 - p1 + 1) > 2) {
//            assert(0);
//        }
//    }

//    fr (i, 1, n) {
//        int cnt = 0;
//        fr (j, 1, n) {
//            if (i == j) continue;
//
//            if (a[j].fi <= a[i].se && a[i].se <= a[j].se) {
//                cnt++;
//            }
//        }
//        assert(cnt <= 1);
//    }

    fr (i, 1, q) {
        int s, e;
        cin >> s >> e;

        if (s == e) {
            ans[i] = 0;
            continue;
        }

        if (a[s].se >= a[e].fi && a[s].se <= a[e].se) {
            ans[i] = 1;
            continue;
        }

        if (a[s].se > a[e].se) {
            ans[i] = -1;
            continue;
        }
        Q[e].pb({s, i});
    }


    sort(all(order), [](int i, int j) {
        return a[i].se < a[j].se || (a[i].se == a[j].se && a[i].fi < a[j].fi);
    });

    fr (i, 1, n) {
        to[i] = i;
        d[i] = 0;
    }

//    subtask1 = 1;

    if (q > 100 && n > 5000) {
        subtask1 = 1;
    }

    ve<pii> add, del;
    fr (idx, 0, sz(order) - 1) {
        int i = order[idx];

        int l = 0;
        int r = idx - 1;
        while (l < r) {
            int mid = l + ((r - l) >> 1);
            int j = order[mid];

            if (a[j].se < a[i].fi) {
                l = mid + 1;
            } else {
                r = mid;
            }
        }

        if (a[order[l]].se < a[i].fi) {
            l++;
        }

        if (l <= idx - 1) {

            if (subtask1) {
                rf (ptr, idx - 1, l) {
                    int j = order[ptr];
                    to[j] = i;
                    d[j] = 1;
                }
            } else {
                add.pb({l, idx});
                del.pb({idx, idx});
            }
        }

//        rf (ptr, idx - 1, 0) {
//            int j = order[ptr];
//            if (a[j].se < a[i].fi) {
//                break;
//            }
//
//            subtask1 &= ptr == idx - 1;
//            to[j] = i;
//            d[j] = 1;
//        }

        if (!subtask1 && sz(Q[i])) {
            sort(all(add));
            sort(all(del));
//
            int ptr1 = 0;
            int ptr2 = 0;
            set<int> s;
            fr (cur, 0, idx) {
                while (ptr1 < sz(add) && add[ptr1].fi <= cur) {
                    s.insert(add[ptr1].se);
                    ptr1++;
                }
                while (ptr2 < sz(del) && del[ptr2].fi <= cur) {
                    s.erase(del[ptr2].se);
                    ptr2++;
                }

                int i = order[cur];

                if (sz(s)) {
                    d[i] = 1;
//                    assert(to[i] == order[*s.rbegin()]);
                    to[i] = order[*s.rbegin()];
                }
            }

            add.clear();
            del.clear();
        }

        fe (cur, Q[i]) {
            if (subtask1) {
                auto p = get(cur.fi);

                if (p.fi == i) {
                    ans[cur.se] = p.se;
                } else {
                    ans[cur.se] = -1;
                }
            } else {
                int v = cur.fi;
                int sum = 0;
                while (to[v] != v) {
                    sum += d[v];
                    v = to[v];
                }

                if (v == i) {
                    ans[cur.se] = sum;
                } else {
                    ans[cur.se] = -1;
                }
            }
        }
    }

    fr (i, 1, q) {
        if (ans[i] == -1) {
            cout << "impossible\n";
        } else {
            cout << ans[i] << "\n";
        }
    }

    return 0;
}

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2644 KB Output is correct
2 Correct 72 ms 13688 KB Output is correct
3 Correct 79 ms 13636 KB Output is correct
4 Correct 123 ms 13632 KB Output is correct
5 Correct 91 ms 10452 KB Output is correct
6 Correct 71 ms 10112 KB Output is correct
7 Correct 74 ms 9972 KB Output is correct
8 Correct 68 ms 7564 KB Output is correct
9 Correct 70 ms 14084 KB Output is correct
10 Correct 86 ms 13964 KB Output is correct
11 Correct 77 ms 7816 KB Output is correct
12 Correct 44 ms 8116 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 2644 KB Output is correct
2 Correct 1 ms 2644 KB Output is correct
3 Correct 2 ms 2772 KB Output is correct
4 Correct 2 ms 2772 KB Output is correct
5 Correct 2 ms 2644 KB Output is correct
6 Correct 2 ms 2644 KB Output is correct
7 Correct 2 ms 2644 KB Output is correct
8 Correct 2 ms 2772 KB Output is correct
9 Correct 2 ms 2644 KB Output is correct

Subtask #3
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 2644 KB Output is correct
2 Correct 1 ms 2644 KB Output is correct
3 Correct 2 ms 2772 KB Output is correct
4 Correct 2 ms 2772 KB Output is correct
5 Correct 2 ms 2644 KB Output is correct
6 Correct 2 ms 2644 KB Output is correct
7 Correct 2 ms 2644 KB Output is correct
8 Correct 2 ms 2772 KB Output is correct
9 Correct 2 ms 2644 KB Output is correct
10 Correct 1 ms 2644 KB Output is correct
11 Correct 1 ms 2644 KB Output is correct
12 Correct 2 ms 2772 KB Output is correct
13 Correct 2 ms 2772 KB Output is correct
14 Correct 2 ms 2644 KB Output is correct
15 Correct 2 ms 2644 KB Output is correct
16 Correct 3 ms 2644 KB Output is correct
17 Correct 2 ms 2772 KB Output is correct
18 Correct 2 ms 2644 KB Output is correct
19 Correct 454 ms 5056 KB Output is correct
20 Correct 32 ms 3716 KB Output is correct
21 Correct 297 ms 4680 KB Output is correct
22 Correct 68 ms 4440 KB Output is correct
23 Correct 80 ms 4084 KB Output is correct
24 Correct 23 ms 3908 KB Output is correct
25 Correct 27 ms 3532 KB Output is correct

Subtask #4
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 2644 KB Output is correct
2 Correct 1 ms 2644 KB Output is correct
3 Correct 2 ms 2772 KB Output is correct
4 Correct 2 ms 2772 KB Output is correct
5 Correct 2 ms 2644 KB Output is correct
6 Correct 2 ms 2644 KB Output is correct
7 Correct 2 ms 2644 KB Output is correct
8 Correct 2 ms 2772 KB Output is correct
9 Correct 2 ms 2644 KB Output is correct
10 Correct 2 ms 2768 KB Output is correct
11 Correct 1 ms 2644 KB Output is correct
12 Correct 2 ms 2772 KB Output is correct
13 Correct 2 ms 2772 KB Output is correct
14 Correct 2 ms 2644 KB Output is correct
15 Correct 2 ms 2644 KB Output is correct
16 Correct 2 ms 2644 KB Output is correct
17 Correct 2 ms 2772 KB Output is correct
18 Correct 2 ms 2644 KB Output is correct
19 Correct 51 ms 13048 KB Output is correct
20 Correct 84 ms 5312 KB Output is correct
21 Correct 91 ms 5252 KB Output is correct
22 Correct 66 ms 5520 KB Output is correct
23 Correct 54 ms 12992 KB Output is correct
24 Correct 47 ms 13056 KB Output is correct
25 Correct 28 ms 7356 KB Output is correct

Subtask #5
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 80 ms 13596 KB Output is correct
2 Correct 82 ms 13760 KB Output is correct
3 Correct 111 ms 13620 KB Output is correct
4 Correct 72 ms 14084 KB Output is correct
5 Correct 87 ms 14020 KB Output is correct
6 Correct 91 ms 13804 KB Output is correct
7 Correct 96 ms 13760 KB Output is correct
8 Correct 90 ms 13940 KB Output is correct
9 Correct 48 ms 13056 KB Output is correct
10 Correct 86 ms 13440 KB Output is correct
11 Correct 70 ms 13196 KB Output is correct
12 Correct 83 ms 13644 KB Output is correct

Subtask #6
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2644 KB Output is correct
2 Correct 72 ms 13688 KB Output is correct
3 Correct 79 ms 13636 KB Output is correct
4 Correct 123 ms 13632 KB Output is correct
5 Correct 91 ms 10452 KB Output is correct
6 Correct 71 ms 10112 KB Output is correct
7 Correct 74 ms 9972 KB Output is correct
8 Correct 68 ms 7564 KB Output is correct
9 Correct 70 ms 14084 KB Output is correct
10 Correct 86 ms 13964 KB Output is correct
11 Correct 77 ms 7816 KB Output is correct
12 Correct 44 ms 8116 KB Output is correct
13 Correct 2 ms 2644 KB Output is correct
14 Correct 1 ms 2644 KB Output is correct
15 Correct 2 ms 2772 KB Output is correct
16 Correct 2 ms 2772 KB Output is correct
17 Correct 2 ms 2644 KB Output is correct
18 Correct 2 ms 2644 KB Output is correct
19 Correct 2 ms 2644 KB Output is correct
20 Correct 2 ms 2772 KB Output is correct
21 Correct 2 ms 2644 KB Output is correct
22 Correct 1 ms 2644 KB Output is correct
23 Correct 1 ms 2644 KB Output is correct
24 Correct 2 ms 2772 KB Output is correct
25 Correct 2 ms 2772 KB Output is correct
26 Correct 2 ms 2644 KB Output is correct
27 Correct 2 ms 2644 KB Output is correct
28 Correct 3 ms 2644 KB Output is correct
29 Correct 2 ms 2772 KB Output is correct
30 Correct 2 ms 2644 KB Output is correct
31 Correct 454 ms 5056 KB Output is correct
32 Correct 32 ms 3716 KB Output is correct
33 Correct 297 ms 4680 KB Output is correct
34 Correct 68 ms 4440 KB Output is correct
35 Correct 80 ms 4084 KB Output is correct
36 Correct 23 ms 3908 KB Output is correct
37 Correct 27 ms 3532 KB Output is correct
38 Correct 2 ms 2768 KB Output is correct
39 Correct 1 ms 2644 KB Output is correct
40 Correct 2 ms 2772 KB Output is correct
41 Correct 2 ms 2772 KB Output is correct
42 Correct 2 ms 2644 KB Output is correct
43 Correct 2 ms 2644 KB Output is correct
44 Correct 2 ms 2644 KB Output is correct
45 Correct 2 ms 2772 KB Output is correct
46 Correct 2 ms 2644 KB Output is correct
47 Correct 51 ms 13048 KB Output is correct
48 Correct 84 ms 5312 KB Output is correct
49 Correct 91 ms 5252 KB Output is correct
50 Correct 66 ms 5520 KB Output is correct
51 Correct 54 ms 12992 KB Output is correct
52 Correct 47 ms 13056 KB Output is correct
53 Correct 28 ms 7356 KB Output is correct
54 Correct 80 ms 13596 KB Output is correct
55 Correct 82 ms 13760 KB Output is correct
56 Correct 111 ms 13620 KB Output is correct
57 Correct 72 ms 14084 KB Output is correct
58 Correct 87 ms 14020 KB Output is correct
59 Correct 91 ms 13804 KB Output is correct
60 Correct 96 ms 13760 KB Output is correct
61 Correct 90 ms 13940 KB Output is correct
62 Correct 48 ms 13056 KB Output is correct
63 Correct 86 ms 13440 KB Output is correct
64 Correct 70 ms 13196 KB Output is correct
65 Correct 83 ms 13644 KB Output is correct
66 Correct 1 ms 2644 KB Output is correct
67 Correct 94 ms 16768 KB Output is correct
68 Correct 86 ms 16696 KB Output is correct
69 Correct 132 ms 16772 KB Output is correct
70 Correct 80 ms 13564 KB Output is correct
71 Correct 88 ms 13160 KB Output is correct
72 Correct 73 ms 13084 KB Output is correct
73 Correct 63 ms 10628 KB Output is correct
74 Correct 72 ms 17264 KB Output is correct
75 Correct 103 ms 17132 KB Output is correct
76 Correct 77 ms 10932 KB Output is correct
77 Correct 46 ms 10444 KB Output is correct
78 Correct 2 ms 2644 KB Output is correct
79 Correct 2 ms 2772 KB Output is correct
80 Correct 2 ms 2800 KB Output is correct
81 Correct 2 ms 2644 KB Output is correct
82 Correct 2 ms 2644 KB Output is correct
83 Correct 2 ms 2772 KB Output is correct
84 Correct 2 ms 2772 KB Output is correct
85 Correct 2 ms 2772 KB Output is correct
86 Correct 445 ms 5948 KB Output is correct
87 Correct 29 ms 4712 KB Output is correct
88 Correct 301 ms 5644 KB Output is correct
89 Correct 76 ms 5424 KB Output is correct
90 Correct 86 ms 5120 KB Output is correct
91 Correct 26 ms 4928 KB Output is correct
92 Correct 27 ms 4504 KB Output is correct
93 Correct 54 ms 15200 KB Output is correct
94 Correct 86 ms 6456 KB Output is correct
95 Correct 92 ms 7100 KB Output is correct
96 Correct 68 ms 7532 KB Output is correct
97 Correct 52 ms 15020 KB Output is correct
98 Correct 48 ms 14908 KB Output is correct
99 Correct 31 ms 8696 KB Output is correct
100 Correct 94 ms 16864 KB Output is correct
101 Correct 87 ms 16900 KB Output is correct
102 Correct 86 ms 16968 KB Output is correct
103 Correct 95 ms 16484 KB Output is correct
104 Correct 94 ms 16316 KB Output is correct
105 Correct 96 ms 16536 KB Output is correct
106 Execution timed out 1563 ms 8528 KB Time limit exceeded
107 Halted 0 ms 0 KB -