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Submission #677063

# Submission time Handle Problem Language Result Execution time Memory
677063 2023-01-02T08:16:13 Z Do_you_copy Event Hopping (BOI22_events) C++17
25 / 100
 385 ms 15348 KB 
//Then
#include <bits/stdc++.h>
#define pb push_back
#define fi first
#define se second
#define faster ios_base::sync_with_stdio(0); cin.tie(0);

using namespace std;
using ll = long long;
using ld = long double;
using pii = pair <int, int>;
mt19937_64 Rand(chrono::steady_clock::now().time_since_epoch().count());
const int maxN = 1e5 + 1;
//const int Mod = 1e9 + 7;
//const int inf =
int n, q;
bool invalid[maxN];
pii e[maxN];
int lift[maxN][20];
vector <int> node;
int st[maxN * 4];

void update(int id, int i, int x, int l = 1, int r = node.size()){
    if (l == r){
        if (e[st[id]].fi > e[x].fi) st[id] = x;
        return;
    }
    int mid = (l + r) >> 1;
    if (i <= mid) update(id << 1, i, x, l, mid);
    else update(id << 1 | 1, i, x, mid + 1, r);
    if (e[st[id << 1]].fi < e[st[id << 1 | 1]].fi) st[id] = st[id << 1];
    else st[id] = st[id << 1 | 1];
}

int get(int id, int i, int j, int l = 1, int r = node.size()){
    if (i > r || l > j) return 0;
    if (i <= l && r <= j) return st[id];
    int mid = (l + r) >> 1;
    int x = get(id << 1, i, j, l, mid);
    int y = get(id << 1 | 1, i, j, mid + 1, r);
    if (e[x].fi < e[y].fi) return x;
    else return y;
}

void Init(){
    cin >> n >> q;
    for (int i = 1; i <= n; ++i){
        cin >> e[i].fi >> e[i].se;
        node.pb(e[i].fi);
        node.pb(e[i].se);
    }
    e[0].fi = INT_MAX;
    sort(node.begin(), node.end());
    node.resize(unique(node.begin(), node.end()) - node.begin());
    for (int i = 1; i <= n; ++i){
        e[i].fi = upper_bound(node.begin(), node.end(), e[i].fi) - node.begin();
        e[i].se = upper_bound(node.begin(), node.end(), e[i].se) - node.begin();
        update(1, e[i].se, i);
    }
    for (int i = 1; i <= n; ++i){
        int u = get(1, e[i].fi, e[i].se);
        if (e[u].fi == e[i].fi) continue; lift[i][0] = i;
        lift[i][0] = u;
    }
    for (int i = 1; i < 20; ++i){
        for (int j = 1; j <= n; ++j){
            lift[j][i] = lift[lift[j][i - 1]][i - 1];
        }
    }
    for (int i = 1; i <= n; ++i) cerr << lift[i][0] << "\n";
    e[0].fi = 0;
    while (q--){
        int s, t;
        cin >> s >> t;
        if (s == t){
            cout << "0\n"; continue;
        }
        if (e[t].se < e[s].se){
            cout << "impossible\n"; continue;
        }
        if (e[t].fi <= e[s].se){
            cout << "1\n"; continue;
        }
        int ans = 0;
        for (int i = 19; i >= 0; --i){
            if (e[lift[t][i]].fi > e[s].se){
                t = lift[t][i];
                ans += 1 << i;
            }
        }
        t = lift[t][0];
        if (t == 0){
            cout << "impossible\n"; continue;
        }
        cout << ans + 2 << "\n";
    }
}

#define debug
#define taskname "test"
signed main(){
    faster
    if (fopen(taskname".inp", "r")){
        freopen(taskname".inp", "r", stdin);
        freopen(taskname".out", "w", stdout);
    }
    int tt = 1;
    //cin >> tt;
    while (tt--){
        Init();
    }
    if (fopen("timeout.txt", "r")){
        ofstream timeout("timeout.txt");
        timeout << signed(double(clock()) / CLOCKS_PER_SEC * 1000);
        timeout.close();
        #ifndef debug
        cerr << "Time elapsed: " << signed(double(clock()) / CLOCKS_PER_SEC * 1000) << "ms\n";
        #endif // debug
    }
}

Compilation message

events.cpp: In function 'void Init()':
events.cpp:62:9: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
   62 |         if (e[u].fi == e[i].fi) continue; lift[i][0] = i;
      |         ^~
events.cpp:62:43: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
   62 |         if (e[u].fi == e[i].fi) continue; lift[i][0] = i;
      |                                           ^~~~
events.cpp: In function 'int main()':
events.cpp:104:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  104 |         freopen(taskname".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
events.cpp:105:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  105 |         freopen(taskname".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Correct 352 ms 15348 KB Output is correct
3 Correct 358 ms 15172 KB Output is correct
4 Correct 385 ms 15076 KB Output is correct
5 Correct 362 ms 15196 KB Output is correct
6 Correct 355 ms 15172 KB Output is correct
7 Correct 359 ms 15172 KB Output is correct
8 Runtime error 43 ms 10204 KB Execution killed with signal 11
9 Halted 0 ms 0 KB -

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 1 ms 340 KB Output is correct
3 Correct 3 ms 468 KB Output is correct
4 Correct 3 ms 468 KB Output is correct
5 Correct 3 ms 468 KB Output is correct
6 Correct 4 ms 468 KB Output is correct
7 Correct 4 ms 468 KB Output is correct
8 Correct 3 ms 468 KB Output is correct
9 Correct 3 ms 468 KB Output is correct

Subtask #3
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 1 ms 340 KB Output is correct
3 Correct 3 ms 468 KB Output is correct
4 Correct 3 ms 468 KB Output is correct
5 Correct 3 ms 468 KB Output is correct
6 Correct 4 ms 468 KB Output is correct
7 Correct 4 ms 468 KB Output is correct
8 Correct 3 ms 468 KB Output is correct
9 Correct 3 ms 468 KB Output is correct
10 Correct 1 ms 340 KB Output is correct
11 Correct 0 ms 340 KB Output is correct
12 Correct 3 ms 468 KB Output is correct
13 Correct 5 ms 468 KB Output is correct
14 Correct 4 ms 468 KB Output is correct
15 Correct 3 ms 484 KB Output is correct
16 Correct 4 ms 468 KB Output is correct
17 Correct 4 ms 372 KB Output is correct
18 Correct 3 ms 352 KB Output is correct
19 Correct 43 ms 2340 KB Output is correct
20 Correct 46 ms 2480 KB Output is correct
21 Correct 42 ms 2636 KB Output is correct
22 Correct 36 ms 2732 KB Output is correct
23 Correct 35 ms 2676 KB Output is correct
24 Correct 33 ms 2644 KB Output is correct
25 Correct 39 ms 2284 KB Output is correct

Subtask #4
0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 1 ms 340 KB Output is correct
3 Correct 3 ms 468 KB Output is correct
4 Correct 3 ms 468 KB Output is correct
5 Correct 3 ms 468 KB Output is correct
6 Correct 4 ms 468 KB Output is correct
7 Correct 4 ms 468 KB Output is correct
8 Correct 3 ms 468 KB Output is correct
9 Correct 3 ms 468 KB Output is correct
10 Correct 1 ms 340 KB Output is correct
11 Correct 0 ms 340 KB Output is correct
12 Correct 3 ms 480 KB Output is correct
13 Correct 3 ms 376 KB Output is correct
14 Correct 3 ms 468 KB Output is correct
15 Correct 3 ms 468 KB Output is correct
16 Correct 4 ms 468 KB Output is correct
17 Correct 4 ms 468 KB Output is correct
18 Correct 3 ms 352 KB Output is correct
19 Correct 326 ms 13380 KB Output is correct
20 Correct 324 ms 12604 KB Output is correct
21 Correct 338 ms 13104 KB Output is correct
22 Incorrect 326 ms 13768 KB Output isn't correct
23 Halted 0 ms 0 KB -

Subtask #5
0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 357 ms 15168 KB Output is correct
2 Correct 350 ms 15088 KB Output is correct
3 Correct 380 ms 15112 KB Output is correct
4 Runtime error 57 ms 10224 KB Execution killed with signal 11
5 Halted 0 ms 0 KB -

Subtask #6
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Correct 352 ms 15348 KB Output is correct
3 Correct 358 ms 15172 KB Output is correct
4 Correct 385 ms 15076 KB Output is correct
5 Correct 362 ms 15196 KB Output is correct
6 Correct 355 ms 15172 KB Output is correct
7 Correct 359 ms 15172 KB Output is correct
8 Runtime error 43 ms 10204 KB Execution killed with signal 11
9 Halted 0 ms 0 KB -