// Om Namah Shivaya
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
template<typename T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long int ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define pb push_back
#define endl '\n'
#define sz(a) a.size()
#define setbits(x) __builtin_popcountll(x)
#define ff first
#define ss second
#define conts continue
#define ceil2(x, y) ((x + y - 1) / (y))
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "Yes" << endl
#define no cout << "No" << endl
#define rep(i, n) for(int i = 0; i < n; ++i)
#define rep1(i, n) for(int i = 1; i <= n; ++i)
#define rev(i, s, e) for(int i = s; i >= e; --i)
#define trav(i, a) for(auto &i : a)
template<typename T>
void amin(T &a, T b) {
a = min(a, b);
}
template<typename T>
void amax(T &a, T b) {
a = max(a, b);
}
#ifdef LOCAL
#include "debug.h"
#else
#define debug(x) 42
#endif
/*
*/
const int MOD = 1e9 + 7;
const int N = 1e5 + 5;
const int inf1 = int(1e9) + 5;
const ll inf2 = ll(1e18) + 5;
template<typename T>
struct segtree {
// https://codeforces.com/blog/entry/18051
/*=======================================================*/
struct data {
int a;
};
data neutral = {inf1};
data merge(data &left, data &right) {
data curr;
curr.a = min(left.a,right.a);
return curr;
}
void create(int i, T v) {
tr[i].a = v;
}
void modify(int i, T v) {
amin(tr[i].a, v);
}
/*=======================================================*/
int n;
vector<data> tr;
segtree() {
}
segtree(int siz) {
init(siz);
}
void init(int siz) {
n = siz;
tr.assign(2 * n, neutral);
}
void build(vector<T> &a, int siz) {
rep(i, siz) create(i + n, a[i]);
rev(i, n - 1, 1) tr[i] = merge(tr[i << 1], tr[i << 1 | 1]);
}
void pupd(int i, T v) {
modify(i + n, v);
for (i = (i + n) >> 1; i; i >>= 1) tr[i] = merge(tr[i << 1], tr[i << 1 | 1]);
}
data query(int l, int r) {
data resl = neutral, resr = neutral;
for (l += n, r += n; l <= r; l >>= 1, r >>= 1) {
if (l & 1) resl = merge(resl, tr[l++]);
if (!(r & 1)) resr = merge(tr[r--], resr);
}
return merge(resl, resr);
}
};
void solve(int test_case)
{
int n,q; cin >> n >> q;
vector<pii> a(n+5);
rep1(i,n) cin >> a[i].ff >> a[i].ss;
vector<int> b;
rep1(i,n) b.pb(a[i].ff), b.pb(a[i].ss);
sort(all(b));
b.resize(unique(all(b))-b.begin());
int siz = sz(b);
rep1(i,n){
a[i].ff = lower_bound(all(b),a[i].ff) - b.begin();
a[i].ss = lower_bound(all(b),a[i].ss) - b.begin();
}
vector<pii> order;
rep1(i,n) order.pb({a[i].ss, i});
sort(all(order));
while(q--){
int u,v; cin >> u >> v;
if(u == v){
cout << 0 << endl;
conts;
}
vector<int> dp(n+5,inf1);
dp[u] = 0;
segtree<int> st(siz+5);
st.pupd(a[u].ss, 0);
for(auto [val, i] : order){
if(i == u or i == v) conts;
int best = st.query(a[i].ff, a[i].ss).a;
dp[i] = best + 1;
st.pupd(a[i].ss, dp[i]);
}
{
int i = v;
int best = st.query(a[i].ff, a[i].ss).a;
dp[i] = best + 1;
st.pupd(a[i].ss, dp[i]);
}
int ans = dp[v];
if(ans <= n){
cout << ans << endl;
}
else{
cout << "impossible" << endl;
}
}
}
int main()
{
fastio;
int t = 1;
// cin >> t;
rep1(i, t) {
solve(i);
}
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
336 KB |
Output is correct |
2 |
Execution timed out |
1584 ms |
3812 KB |
Time limit exceeded |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
212 KB |
Output is correct |
2 |
Correct |
1 ms |
212 KB |
Output is correct |
3 |
Correct |
4 ms |
340 KB |
Output is correct |
4 |
Correct |
5 ms |
340 KB |
Output is correct |
5 |
Correct |
4 ms |
360 KB |
Output is correct |
6 |
Correct |
4 ms |
340 KB |
Output is correct |
7 |
Correct |
9 ms |
340 KB |
Output is correct |
8 |
Correct |
7 ms |
372 KB |
Output is correct |
9 |
Correct |
2 ms |
340 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
212 KB |
Output is correct |
2 |
Correct |
1 ms |
212 KB |
Output is correct |
3 |
Correct |
4 ms |
340 KB |
Output is correct |
4 |
Correct |
5 ms |
340 KB |
Output is correct |
5 |
Correct |
4 ms |
360 KB |
Output is correct |
6 |
Correct |
4 ms |
340 KB |
Output is correct |
7 |
Correct |
9 ms |
340 KB |
Output is correct |
8 |
Correct |
7 ms |
372 KB |
Output is correct |
9 |
Correct |
2 ms |
340 KB |
Output is correct |
10 |
Correct |
0 ms |
212 KB |
Output is correct |
11 |
Correct |
0 ms |
212 KB |
Output is correct |
12 |
Correct |
4 ms |
340 KB |
Output is correct |
13 |
Correct |
4 ms |
340 KB |
Output is correct |
14 |
Correct |
4 ms |
340 KB |
Output is correct |
15 |
Correct |
5 ms |
340 KB |
Output is correct |
16 |
Correct |
9 ms |
340 KB |
Output is correct |
17 |
Correct |
9 ms |
340 KB |
Output is correct |
18 |
Correct |
2 ms |
340 KB |
Output is correct |
19 |
Execution timed out |
1592 ms |
572 KB |
Time limit exceeded |
20 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
212 KB |
Output is correct |
2 |
Correct |
1 ms |
212 KB |
Output is correct |
3 |
Correct |
4 ms |
340 KB |
Output is correct |
4 |
Correct |
5 ms |
340 KB |
Output is correct |
5 |
Correct |
4 ms |
360 KB |
Output is correct |
6 |
Correct |
4 ms |
340 KB |
Output is correct |
7 |
Correct |
9 ms |
340 KB |
Output is correct |
8 |
Correct |
7 ms |
372 KB |
Output is correct |
9 |
Correct |
2 ms |
340 KB |
Output is correct |
10 |
Correct |
1 ms |
212 KB |
Output is correct |
11 |
Correct |
0 ms |
212 KB |
Output is correct |
12 |
Correct |
4 ms |
340 KB |
Output is correct |
13 |
Correct |
4 ms |
340 KB |
Output is correct |
14 |
Correct |
4 ms |
340 KB |
Output is correct |
15 |
Correct |
5 ms |
340 KB |
Output is correct |
16 |
Correct |
9 ms |
340 KB |
Output is correct |
17 |
Correct |
7 ms |
340 KB |
Output is correct |
18 |
Correct |
2 ms |
340 KB |
Output is correct |
19 |
Correct |
561 ms |
3856 KB |
Output is correct |
20 |
Correct |
588 ms |
5008 KB |
Output is correct |
21 |
Correct |
874 ms |
5812 KB |
Output is correct |
22 |
Correct |
644 ms |
6160 KB |
Output is correct |
23 |
Correct |
1166 ms |
6572 KB |
Output is correct |
24 |
Correct |
846 ms |
6572 KB |
Output is correct |
25 |
Correct |
166 ms |
4668 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Execution timed out |
1584 ms |
3804 KB |
Time limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
336 KB |
Output is correct |
2 |
Execution timed out |
1584 ms |
3812 KB |
Time limit exceeded |
3 |
Halted |
0 ms |
0 KB |
- |