#include <bits/stdc++.h>
using namespace std;
const int maxn = 100010, SZ = 300;
int n, q, b[maxn], rmq[20][maxn];
int bel[maxn], bl[maxn], br[maxn];
array<int, 2> a[maxn];
vector<int> tr[maxn];
int main() {
ios::sync_with_stdio(0), cin.tie(0);
cin >> n >> q;
vector<int> V;
for (int i = 1; i <= n; i++) {
cin >> a[i][0] >> a[i][1], V.push_back(a[i][1]);
}
sort(V.begin(), V.end());
V.resize(unique(V.begin(), V.end()) - V.begin());
fill(b + 1, b + n + 1, n + 1);
for (int i = 1; i <= n; i++) {
a[i][0] = lower_bound(V.begin(), V.end(), a[i][0]) - V.begin() + 1;
a[i][1] = lower_bound(V.begin(), V.end(), a[i][1]) - V.begin() + 1;
b[a[i][1]] = min(b[a[i][1]], a[i][0]);
}
for (int i = 1; i <= n; i++) {
br[bel[i] = (i - 1) / SZ + 1] = i;
if (!bl[bel[i]]) bl[bel[i]] = i;
}
copy(b + 1, b + n + 1, rmq[0] + 1);
for (int k = 1; k < 20; k++) {
for (int i = 1; i + (1 << k) - 1 <= n; i++) {
rmq[k][i] = min(rmq[k - 1][i], rmq[k - 1][i + (1 << (k - 1))]);
}
}
auto qmin = [&](int l, int r) {
int k = __lg(r - l + 1);
return min(rmq[k][l], rmq[k][r - (1 << k) + 1]);
};
auto go = [&](int s, int r) {
int lb = s + 1, rb = r, ans = 0;
while (lb <= rb) {
int mid = (lb + rb) / 2;
qmin(mid, r) <= s ? lb = (ans = mid) + 1 : rb = mid - 1;
}
return ans;
};
for (int i = 1; i <= n; i++) {
for (int lim = br[bel[i]], j = go(i, lim); j && j <= lim; j = go(j, lim)) {
tr[i].push_back(j);
}
}
while (q--) {
int s, t, ans = 0;
cin >> s >> t;
if (s == t) { cout << "0\n"; continue; }
for (s = a[s][1]; s && s < a[t][0]; ans++) {
int nxt;
if (bel[s] + 1 >= bel[a[t][0]] || (nxt = qmin(bl[bel[s] + 1], a[t][1])) <= s) {
s = go(s, a[t][1]);
} else {
auto it = lower_bound(tr[s].begin(), tr[s].end(), nxt);
if (it == tr[s].end()) { s = 0; break; }
ans += it - tr[s].begin(), s = *it;
}
}
if (a[t][0] <= s && s <= a[t][1]) cout << ans + 1 << "\n";
else cout << "impossible\n";
}
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
2644 KB |
Output is correct |
2 |
Execution timed out |
1591 ms |
98204 KB |
Time limit exceeded |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
2644 KB |
Output is correct |
2 |
Correct |
1 ms |
2644 KB |
Output is correct |
3 |
Correct |
7 ms |
3544 KB |
Output is correct |
4 |
Correct |
6 ms |
3412 KB |
Output is correct |
5 |
Correct |
7 ms |
3540 KB |
Output is correct |
6 |
Correct |
2 ms |
2772 KB |
Output is correct |
7 |
Correct |
2 ms |
2772 KB |
Output is correct |
8 |
Correct |
2 ms |
2772 KB |
Output is correct |
9 |
Correct |
2 ms |
2772 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
2644 KB |
Output is correct |
2 |
Correct |
1 ms |
2644 KB |
Output is correct |
3 |
Correct |
7 ms |
3544 KB |
Output is correct |
4 |
Correct |
6 ms |
3412 KB |
Output is correct |
5 |
Correct |
7 ms |
3540 KB |
Output is correct |
6 |
Correct |
2 ms |
2772 KB |
Output is correct |
7 |
Correct |
2 ms |
2772 KB |
Output is correct |
8 |
Correct |
2 ms |
2772 KB |
Output is correct |
9 |
Correct |
2 ms |
2772 KB |
Output is correct |
10 |
Correct |
1 ms |
2644 KB |
Output is correct |
11 |
Correct |
1 ms |
2644 KB |
Output is correct |
12 |
Correct |
8 ms |
3508 KB |
Output is correct |
13 |
Correct |
9 ms |
3412 KB |
Output is correct |
14 |
Correct |
7 ms |
3540 KB |
Output is correct |
15 |
Correct |
2 ms |
2772 KB |
Output is correct |
16 |
Correct |
2 ms |
2772 KB |
Output is correct |
17 |
Correct |
3 ms |
2772 KB |
Output is correct |
18 |
Correct |
2 ms |
2772 KB |
Output is correct |
19 |
Execution timed out |
1584 ms |
5036 KB |
Time limit exceeded |
20 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
2644 KB |
Output is correct |
2 |
Correct |
1 ms |
2644 KB |
Output is correct |
3 |
Correct |
7 ms |
3544 KB |
Output is correct |
4 |
Correct |
6 ms |
3412 KB |
Output is correct |
5 |
Correct |
7 ms |
3540 KB |
Output is correct |
6 |
Correct |
2 ms |
2772 KB |
Output is correct |
7 |
Correct |
2 ms |
2772 KB |
Output is correct |
8 |
Correct |
2 ms |
2772 KB |
Output is correct |
9 |
Correct |
2 ms |
2772 KB |
Output is correct |
10 |
Correct |
1 ms |
2644 KB |
Output is correct |
11 |
Correct |
2 ms |
2644 KB |
Output is correct |
12 |
Correct |
7 ms |
3540 KB |
Output is correct |
13 |
Correct |
6 ms |
3412 KB |
Output is correct |
14 |
Correct |
7 ms |
3580 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 |
2772 KB |
Output is correct |
18 |
Correct |
2 ms |
2772 KB |
Output is correct |
19 |
Correct |
507 ms |
97960 KB |
Output is correct |
20 |
Correct |
489 ms |
97972 KB |
Output is correct |
21 |
Correct |
54 ms |
12320 KB |
Output is correct |
22 |
Correct |
375 ms |
65924 KB |
Output is correct |
23 |
Correct |
52 ms |
13852 KB |
Output is correct |
24 |
Correct |
63 ms |
13900 KB |
Output is correct |
25 |
Correct |
25 ms |
10836 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Execution timed out |
1591 ms |
98332 KB |
Time limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
2644 KB |
Output is correct |
2 |
Execution timed out |
1591 ms |
98204 KB |
Time limit exceeded |
3 |
Halted |
0 ms |
0 KB |
- |