#include "bits/stdc++.h"
using namespace std;
#define int long long
const int MAXN = 3e5 + 10;
const int MOD = 998244353;
#define ll __int128
mt19937_64 rng((int)std::chrono::steady_clock::now().time_since_epoch().count());
int rnd(int x, int y) {
int u = uniform_int_distribution<int>(x, y)(rng); return u;
}
ll read() { int x; cin >> x; return (ll)x; }
long long bm(long long b, long long p) {
if(p==0) return 1 % MOD;
long long r = bm(b, p >> 1);
if(p&1) return (((r*r) % MOD) * b) % MOD;
return (r*r) % MOD;
}
long long inv(long long b) {
return bm(b, MOD-2);
}
long long f[MAXN];
long long nCr(int n, int r) {
long long ans = f[n]; ans *= inv(f[r]); ans %= MOD;
ans *= inv(f[n-r]); ans %= MOD; return ans;
}
long long fib[MAXN], lucas[MAXN];
void precomp() {
for(int i=0; i<MAXN; i++) f[i] = (i == 0 ? 1 % MOD : (f[i-1] * i) % MOD);
lucas[0] = 2;
lucas[1] = 1;
for(int i=2; i<MAXN; i++) lucas[i] = (lucas[i-2] + lucas[i-1]) % MOD;
fib[0] = 0;
fib[1] = 1;
for(int i=2; i<MAXN; i++) fib[i] = (fib[i-2] + fib[i-1]) % MOD;
}
int fastlog(int x) {
return (x == 0 ? -1 : 64 - __builtin_clzll(x) - 1);
}
void google(int i) { cout << "Case #" << i << ": "; }
int csb(int l, int r, int k) { // count number of [l, r] such that i & 2^k > 0
if(l > r) return 0;
if(l == 0) {
int s = r / (1ll << (k+1)); // number of complete cycles
int t = r % (1ll << (k+1));
int ans = s * (1ll << k);
ans += (t >= (1ll << k) ? t - (1ll << k) + 1 : 0);
return ans;
}
else return csb(0, r, k) - csb(0, l - 1, k);
}
int lis(vector<int> a) {
int n = a.size();
int bucket[n+1];
for(int i=1; i<=n; i++) bucket[i] = 1e18;
int ans = 1;
for(int x: a) {
auto it = lower_bound(bucket + 1, bucket +n +1, x);
int d = distance(bucket, it);
ans = max(ans, d);
bucket[d] = min(bucket[d], x);
}
return ans;
}
pair<int, int> str[4*MAXN];
void u(int l, int r, int tar, int idx, int val, int val2) {
if(l == r) {
str[idx] = {val, val2}; return;
}
int mid = (l + r) >> 1;
if(tar <= mid) u(l, mid, tar, 2 * idx + 1, val, val2);
else u(mid + 1, r, tar, 2 * idx + 2, val, val2);
str[idx] = min(str[2*idx+1], str[2*idx+2]);
}
pair<int, int> qu(int l, int r, int constl, int constr, int idx) {
if(l <= constl && constr <= r) return str[idx];
int mid = (constl + constr) >> 1;
if(mid < l || r < constl) return qu(l, r, mid+1, constr, 2*idx+2);
else if(constr < l || r < mid+1) return qu(l, r, constl, mid, 2*idx+1);
else {
return min(qu(l, r, constl, mid, 2*idx+1), qu(l, r, mid+1, constr, 2*idx+2));
}
}
void update(int i, int v, int w) {
u(0, MAXN - 1, i, 0, v, w);
}
int min_idx(int l, int r) {
pair<int, int> res = qu(l, r, 0, MAXN - 1, 0);
if(res.first == 1e16) return -1;
return res.second;
}
void solve(int tc) {
int n, q;
cin >> n >> q;
int s[n+1], e[n+1];
for(int i=1; i<=n; i++) cin >> s[i] >> e[i];
set<int> sett;
unordered_map<int, int> is;
int nxt = 0;
for(int i=1; i<=n; i++) {
sett.insert(s[i]);
sett.insert(e[i]);
}
for(int x: sett) {
nxt++;
is[x] = nxt;
}
for(int i=1; i<=n; i++) s[i] = is[s[i]], e[i] = is[e[i]];
int m = nxt;
pair<int, int> ohno1[m+1];
for(int i=1; i<=m; i++) ohno1[i] = {1e16, 0};
for(int i=1; i<=n; i++) ohno1[e[i]] = min(ohno1[e[i]], {s[i], i});
for(int i=1; i<=m; i++) update(i, ohno1[i].first, ohno1[i].second);
int st[17][n+1];
for(int i=1; i<=n; i++) {
st[0][i] = min_idx(s[i], e[i]);
if(s[st[0][i]] == s[i]) st[0][i] = -1;
cout << st[0][i] << " \n"[i == n];
}
for(int i=1; i<17; i++) {
for(int j=1; j<=n; j++) {
if(st[i-1][j] != -1) st[i][j] = st[i-1][st[i-1][j]];
else st[i][j] = -1;
}
}
while(q--) {
int x, y;
cin >> x >> y;
int ans = 0;
if(e[x] > e[y]) {
cout << "impossible\n"; continue;
}
if(x == y) {
cout << "0\n"; continue;
}
if(s[y] <= e[x] && e[x] <= e[y]) {
cout << "1\n"; continue;
}
for(int i=16; i>=0; i--) {
int id = st[i][y];
if(id == -1) continue;
if(s[id] > e[x]) {
y = id;
ans += (1 << i);
}
}
//cout << x << " " << y << " " << ans << "\n";
if(x == y) {
cout << ans << "\n"; continue;
}
if(s[y] <= e[x] && e[x] <= e[y]) {
cout << ans + 1 << "\n"; continue;
}
bool done = 0;
for(int i=0; i<3; i++) {
y = st[0][y];
ans++;
if(y == -1) {
break;
}
if(s[y] <= e[x] && e[x] <= e[y]) {
cout << ans + 1 << "\n";
done = 1;
break;
}
}
if(!done) cout << "impossible\n";
}
}
int32_t main() {
precomp();
ios::sync_with_stdio(0); cin.tie(0);
int t = 1; //cin >> t;
for(int i=1; i<=t; i++) solve(i);
}
// I don't know geometry.
// Teaming is unfair.
/*
*/
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
7 ms |
7380 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
9 ms |
7380 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
9 ms |
7380 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
9 ms |
7380 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
163 ms |
40568 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
7 ms |
7380 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
