#include<bits/stdc++.h>
using namespace std;
const long long inf = (long long) 1e18 + 10;
const int inf1 = (int) 1e9 + 10;
#define int long long
#define dbl long double
#define endl '\n'
#define sc second
#define fr first
#define mp make_pair
#define pb push_back
#define all(x) x.begin(), x.end()
const int maxn = 2e5+10;
int n, q, idord[maxn], lf[maxn], rg[maxn], nx[maxn][25], pv[maxn][25];
pair<int,int> trmn[4*maxn],trmx[4*maxn];
void buildmx(int no, int l, int r) {
trmx[no] = mp(-inf,0);
if(l == r) return;
int lc=2*no,rc=2*no+1,mid=(l+r)/2;
buildmx(lc,l,mid);
buildmx(rc,mid+1,r);
}
void updmx(int no, int l, int r, int pos, pair<int,int> val) {
if(l > pos || r < pos) return;
if(l == r) {
trmx[no] = max(trmx[no],val);
return;
}
int lc=2*no,rc=2*no+1,mid=(l+r)/2;
updmx(lc,l,mid,pos,val);
updmx(rc,mid+1,r,pos,val);
trmx[no] = max(trmx[lc],trmx[rc]);
}
pair<int,int> qrymx(int no, int l, int r, int L, int R) {
if(l > R || r < L) return mp(-inf,0);
if(l >= L && r <= R) return trmx[no];
int lc=2*no,rc=2*no+1,mid=(l+r)/2;
return max(qrymx(lc,l,mid,L,R),qrymx(rc,mid+1,r,L,R));
}
void buildmn(int no, int l, int r) {
trmn[no] = mp(inf,0);
if(l == r) return;
int lc=2*no,rc=2*no+1,mid=(l+r)/2;
buildmn(lc,l,mid);
buildmn(rc,mid+1,r);
}
void updmn(int no, int l, int r, int pos, pair<int,int> val) {
if(l > pos || r < pos) return;
if(l == r) {
trmn[no] = min(trmn[no],val);
return;
}
int lc=2*no,rc=2*no+1,mid=(l+r)/2;
updmn(lc,l,mid,pos,val);
updmn(rc,mid+1,r,pos,val);
trmn[no] = min(trmn[lc],trmn[rc]);
}
pair<int,int> qrymn(int no, int l, int r, int L, int R) {
if(l > R || r < L) return mp(inf,0);
if(l >= L && r <= R) return trmn[no];
int lc=2*no,rc=2*no+1,mid=(l+r)/2;
return min(qrymn(lc,l,mid,L,R),qrymn(rc,mid+1,r,L,R));
}
void solve() {
cin >> n >> q;
vector<pair<pair<int,int>,int>> ord;
vector<int> cc;
for(int i = 1; i <= n; i++) {
int l, r; cin >> l >> r;
ord.pb(mp(mp(r,l),i));
lf[i] = l;
rg[i] = r;
cc.pb(lf[i]);
cc.pb(rg[i]);
}
sort(all(cc));
cc.erase(unique(all(cc)),cc.end());
int mxv = cc.size();
for(int i = 1; i <= n; i++) {
lf[i] = upper_bound(all(cc),lf[i])-cc.begin();
rg[i] = upper_bound(all(cc),rg[i])-cc.begin();
}
// sort(all(ord));
buildmx(1,1,mxv);
buildmn(1,1,mxv);
for(int i = 1; i <= n; i++) {
updmx(1,1,mxv,lf[i],mp(rg[i],i));
updmn(1,1,mxv,rg[i],mp(lf[i],i));
}
for(int i = 1; i <= n; i++) {
nx[i][0] = 0;
// for(int j = 1; j <= n; j++) {
// if(lf[j] <= rg[i] && rg[j] > rg[i]) {
// if(nx[i][0] == 0 || rg[j] > rg[nx[i][0]]) nx[i][0] = j;
// }
// }
auto valnx = qrymx(1,1,mxv,1,rg[i]);
if(valnx.fr == rg[i]) nx[i][0] = 0;
else nx[i][0] = valnx.sc;
pv[i][0] = 0;
// for(int j = 1; j <= n; j++) {
// if(j == i || !(lf[i] <= rg[j] && rg[j] <= rg[i]) || !(lf[j] < lf[i])) continue;
// if(pv[i][0] == 0 || lf[j] < lf[pv[i][0]]) pv[i][0] = j;
// }
auto valpv = qrymn(1,1,mxv,lf[i],rg[i]);
if(valpv.fr == lf[i]) pv[i][0] = 0;
else pv[i][0] = valpv.sc;
// cout << i << " " << nx[i][0] << " " << pv[i][0] << endl;
}
for(int j = 1; j <= 20; j++) {
for(int i = 1; i <= n; i++) {
nx[i][j] = nx[nx[i][j-1]][j-1];
pv[i][j] = pv[pv[i][j-1]][j-1];
}
}
while(q--) {
int s,e; cin >> s >> e;
int ans = 0;
for(int j = 20; j >= 0; j--) {
if(nx[s][j] != 0 && rg[nx[s][j]] < rg[e]) {
ans+= (1<<j);
s = nx[s][j];
}
}
for(int j = 20; j >= 0; j--) {
if(pv[e][j] != 0 && lf[pv[e][j]] > lf[s]) {
ans+= (1<<j);
e = pv[e][j];
}
}
if(s == e) {
cout << ans << endl;
}
else if(lf[e] <= rg[s] && rg[s] <= rg[e]) {
cout << ans+1 << endl;
}
else if(nx[s][0] != 0 && lf[e] <= rg[nx[s][0]] && rg[nx[s][0]] <= rg[e]) {
cout << ans+2 << endl;
}
else if(pv[e][0] != 0 && lf[pv[e][0]] <= rg[s] && rg[s] <= rg[pv[e][0]]) {
cout << ans+2 << endl;
}
else {
cout << "impossible" << endl;
}
}
}
int32_t main() {
ios::sync_with_stdio(false); cin.tie(0);
// freopen("in.in", "r", stdin);
// freopen("out.out", "w", stdout);
int tt = 1;
// cin >> tt;
while(tt--) {
solve();
}
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
340 KB |
Output is correct |
2 |
Correct |
237 ms |
53976 KB |
Output is correct |
3 |
Correct |
258 ms |
57100 KB |
Output is correct |
4 |
Correct |
313 ms |
57104 KB |
Output is correct |
5 |
Correct |
260 ms |
57108 KB |
Output is correct |
6 |
Correct |
266 ms |
57260 KB |
Output is correct |
7 |
Correct |
276 ms |
57200 KB |
Output is correct |
8 |
Correct |
258 ms |
65768 KB |
Output is correct |
9 |
Correct |
247 ms |
65712 KB |
Output is correct |
10 |
Correct |
308 ms |
57480 KB |
Output is correct |
11 |
Correct |
315 ms |
65632 KB |
Output is correct |
12 |
Correct |
165 ms |
56824 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
340 KB |
Output is correct |
2 |
Correct |
1 ms |
340 KB |
Output is correct |
3 |
Correct |
1 ms |
852 KB |
Output is correct |
4 |
Correct |
2 ms |
852 KB |
Output is correct |
5 |
Correct |
1 ms |
852 KB |
Output is correct |
6 |
Correct |
3 ms |
852 KB |
Output is correct |
7 |
Correct |
2 ms |
852 KB |
Output is correct |
8 |
Correct |
2 ms |
940 KB |
Output is correct |
9 |
Correct |
1 ms |
724 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
340 KB |
Output is correct |
2 |
Correct |
1 ms |
340 KB |
Output is correct |
3 |
Correct |
1 ms |
852 KB |
Output is correct |
4 |
Correct |
2 ms |
852 KB |
Output is correct |
5 |
Correct |
1 ms |
852 KB |
Output is correct |
6 |
Correct |
3 ms |
852 KB |
Output is correct |
7 |
Correct |
2 ms |
852 KB |
Output is correct |
8 |
Correct |
2 ms |
940 KB |
Output is correct |
9 |
Correct |
1 ms |
724 KB |
Output is correct |
10 |
Correct |
0 ms |
340 KB |
Output is correct |
11 |
Correct |
1 ms |
340 KB |
Output is correct |
12 |
Correct |
1 ms |
852 KB |
Output is correct |
13 |
Correct |
2 ms |
852 KB |
Output is correct |
14 |
Correct |
2 ms |
852 KB |
Output is correct |
15 |
Correct |
1 ms |
852 KB |
Output is correct |
16 |
Correct |
2 ms |
852 KB |
Output is correct |
17 |
Correct |
2 ms |
852 KB |
Output is correct |
18 |
Correct |
1 ms |
724 KB |
Output is correct |
19 |
Correct |
37 ms |
3676 KB |
Output is correct |
20 |
Correct |
39 ms |
3744 KB |
Output is correct |
21 |
Correct |
43 ms |
3880 KB |
Output is correct |
22 |
Correct |
37 ms |
3960 KB |
Output is correct |
23 |
Correct |
39 ms |
4364 KB |
Output is correct |
24 |
Correct |
35 ms |
4392 KB |
Output is correct |
25 |
Correct |
33 ms |
3944 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
340 KB |
Output is correct |
2 |
Correct |
1 ms |
340 KB |
Output is correct |
3 |
Correct |
1 ms |
852 KB |
Output is correct |
4 |
Correct |
2 ms |
852 KB |
Output is correct |
5 |
Correct |
1 ms |
852 KB |
Output is correct |
6 |
Correct |
3 ms |
852 KB |
Output is correct |
7 |
Correct |
2 ms |
852 KB |
Output is correct |
8 |
Correct |
2 ms |
940 KB |
Output is correct |
9 |
Correct |
1 ms |
724 KB |
Output is correct |
10 |
Correct |
0 ms |
340 KB |
Output is correct |
11 |
Correct |
1 ms |
340 KB |
Output is correct |
12 |
Correct |
1 ms |
852 KB |
Output is correct |
13 |
Correct |
2 ms |
852 KB |
Output is correct |
14 |
Correct |
1 ms |
852 KB |
Output is correct |
15 |
Correct |
2 ms |
852 KB |
Output is correct |
16 |
Correct |
2 ms |
928 KB |
Output is correct |
17 |
Correct |
2 ms |
852 KB |
Output is correct |
18 |
Correct |
1 ms |
724 KB |
Output is correct |
19 |
Correct |
212 ms |
53380 KB |
Output is correct |
20 |
Correct |
207 ms |
54496 KB |
Output is correct |
21 |
Correct |
229 ms |
55240 KB |
Output is correct |
22 |
Correct |
227 ms |
63516 KB |
Output is correct |
23 |
Correct |
252 ms |
63756 KB |
Output is correct |
24 |
Correct |
248 ms |
63560 KB |
Output is correct |
25 |
Correct |
71 ms |
46456 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
246 ms |
53888 KB |
Output is correct |
2 |
Correct |
261 ms |
54464 KB |
Output is correct |
3 |
Correct |
303 ms |
54444 KB |
Output is correct |
4 |
Correct |
256 ms |
63376 KB |
Output is correct |
5 |
Correct |
315 ms |
54868 KB |
Output is correct |
6 |
Correct |
341 ms |
62872 KB |
Output is correct |
7 |
Correct |
332 ms |
62788 KB |
Output is correct |
8 |
Correct |
320 ms |
62876 KB |
Output is correct |
9 |
Correct |
255 ms |
62072 KB |
Output is correct |
10 |
Correct |
296 ms |
62664 KB |
Output is correct |
11 |
Correct |
275 ms |
62196 KB |
Output is correct |
12 |
Correct |
296 ms |
62396 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
340 KB |
Output is correct |
2 |
Correct |
237 ms |
53976 KB |
Output is correct |
3 |
Correct |
258 ms |
57100 KB |
Output is correct |
4 |
Correct |
313 ms |
57104 KB |
Output is correct |
5 |
Correct |
260 ms |
57108 KB |
Output is correct |
6 |
Correct |
266 ms |
57260 KB |
Output is correct |
7 |
Correct |
276 ms |
57200 KB |
Output is correct |
8 |
Correct |
258 ms |
65768 KB |
Output is correct |
9 |
Correct |
247 ms |
65712 KB |
Output is correct |
10 |
Correct |
308 ms |
57480 KB |
Output is correct |
11 |
Correct |
315 ms |
65632 KB |
Output is correct |
12 |
Correct |
165 ms |
56824 KB |
Output is correct |
13 |
Correct |
0 ms |
340 KB |
Output is correct |
14 |
Correct |
1 ms |
340 KB |
Output is correct |
15 |
Correct |
1 ms |
852 KB |
Output is correct |
16 |
Correct |
2 ms |
852 KB |
Output is correct |
17 |
Correct |
1 ms |
852 KB |
Output is correct |
18 |
Correct |
3 ms |
852 KB |
Output is correct |
19 |
Correct |
2 ms |
852 KB |
Output is correct |
20 |
Correct |
2 ms |
940 KB |
Output is correct |
21 |
Correct |
1 ms |
724 KB |
Output is correct |
22 |
Correct |
0 ms |
340 KB |
Output is correct |
23 |
Correct |
1 ms |
340 KB |
Output is correct |
24 |
Correct |
1 ms |
852 KB |
Output is correct |
25 |
Correct |
2 ms |
852 KB |
Output is correct |
26 |
Correct |
2 ms |
852 KB |
Output is correct |
27 |
Correct |
1 ms |
852 KB |
Output is correct |
28 |
Correct |
2 ms |
852 KB |
Output is correct |
29 |
Correct |
2 ms |
852 KB |
Output is correct |
30 |
Correct |
1 ms |
724 KB |
Output is correct |
31 |
Correct |
37 ms |
3676 KB |
Output is correct |
32 |
Correct |
39 ms |
3744 KB |
Output is correct |
33 |
Correct |
43 ms |
3880 KB |
Output is correct |
34 |
Correct |
37 ms |
3960 KB |
Output is correct |
35 |
Correct |
39 ms |
4364 KB |
Output is correct |
36 |
Correct |
35 ms |
4392 KB |
Output is correct |
37 |
Correct |
33 ms |
3944 KB |
Output is correct |
38 |
Correct |
0 ms |
340 KB |
Output is correct |
39 |
Correct |
1 ms |
340 KB |
Output is correct |
40 |
Correct |
1 ms |
852 KB |
Output is correct |
41 |
Correct |
2 ms |
852 KB |
Output is correct |
42 |
Correct |
1 ms |
852 KB |
Output is correct |
43 |
Correct |
2 ms |
852 KB |
Output is correct |
44 |
Correct |
2 ms |
928 KB |
Output is correct |
45 |
Correct |
2 ms |
852 KB |
Output is correct |
46 |
Correct |
1 ms |
724 KB |
Output is correct |
47 |
Correct |
212 ms |
53380 KB |
Output is correct |
48 |
Correct |
207 ms |
54496 KB |
Output is correct |
49 |
Correct |
229 ms |
55240 KB |
Output is correct |
50 |
Correct |
227 ms |
63516 KB |
Output is correct |
51 |
Correct |
252 ms |
63756 KB |
Output is correct |
52 |
Correct |
248 ms |
63560 KB |
Output is correct |
53 |
Correct |
71 ms |
46456 KB |
Output is correct |
54 |
Correct |
246 ms |
53888 KB |
Output is correct |
55 |
Correct |
261 ms |
54464 KB |
Output is correct |
56 |
Correct |
303 ms |
54444 KB |
Output is correct |
57 |
Correct |
256 ms |
63376 KB |
Output is correct |
58 |
Correct |
315 ms |
54868 KB |
Output is correct |
59 |
Correct |
341 ms |
62872 KB |
Output is correct |
60 |
Correct |
332 ms |
62788 KB |
Output is correct |
61 |
Correct |
320 ms |
62876 KB |
Output is correct |
62 |
Correct |
255 ms |
62072 KB |
Output is correct |
63 |
Correct |
296 ms |
62664 KB |
Output is correct |
64 |
Correct |
275 ms |
62196 KB |
Output is correct |
65 |
Correct |
296 ms |
62396 KB |
Output is correct |
66 |
Correct |
1 ms |
340 KB |
Output is correct |
67 |
Correct |
241 ms |
57108 KB |
Output is correct |
68 |
Correct |
261 ms |
56984 KB |
Output is correct |
69 |
Correct |
314 ms |
57076 KB |
Output is correct |
70 |
Correct |
263 ms |
57132 KB |
Output is correct |
71 |
Correct |
274 ms |
57248 KB |
Output is correct |
72 |
Correct |
261 ms |
57088 KB |
Output is correct |
73 |
Correct |
271 ms |
65816 KB |
Output is correct |
74 |
Correct |
250 ms |
65796 KB |
Output is correct |
75 |
Correct |
301 ms |
57444 KB |
Output is correct |
76 |
Correct |
301 ms |
65724 KB |
Output is correct |
77 |
Correct |
162 ms |
56708 KB |
Output is correct |
78 |
Correct |
1 ms |
340 KB |
Output is correct |
79 |
Correct |
2 ms |
920 KB |
Output is correct |
80 |
Correct |
2 ms |
856 KB |
Output is correct |
81 |
Correct |
2 ms |
852 KB |
Output is correct |
82 |
Correct |
2 ms |
852 KB |
Output is correct |
83 |
Correct |
2 ms |
924 KB |
Output is correct |
84 |
Correct |
2 ms |
980 KB |
Output is correct |
85 |
Correct |
1 ms |
852 KB |
Output is correct |
86 |
Correct |
39 ms |
4712 KB |
Output is correct |
87 |
Correct |
36 ms |
4680 KB |
Output is correct |
88 |
Correct |
42 ms |
4904 KB |
Output is correct |
89 |
Correct |
36 ms |
4952 KB |
Output is correct |
90 |
Correct |
37 ms |
5388 KB |
Output is correct |
91 |
Correct |
39 ms |
5320 KB |
Output is correct |
92 |
Correct |
34 ms |
5040 KB |
Output is correct |
93 |
Correct |
215 ms |
55472 KB |
Output is correct |
94 |
Correct |
207 ms |
54528 KB |
Output is correct |
95 |
Correct |
229 ms |
55376 KB |
Output is correct |
96 |
Correct |
226 ms |
63432 KB |
Output is correct |
97 |
Correct |
234 ms |
63500 KB |
Output is correct |
98 |
Correct |
253 ms |
63432 KB |
Output is correct |
99 |
Correct |
73 ms |
46444 KB |
Output is correct |
100 |
Correct |
321 ms |
65424 KB |
Output is correct |
101 |
Correct |
311 ms |
65396 KB |
Output is correct |
102 |
Correct |
310 ms |
65736 KB |
Output is correct |
103 |
Correct |
301 ms |
64996 KB |
Output is correct |
104 |
Correct |
274 ms |
64820 KB |
Output is correct |
105 |
Correct |
289 ms |
65132 KB |
Output is correct |
106 |
Correct |
286 ms |
56520 KB |
Output is correct |
107 |
Correct |
301 ms |
56456 KB |
Output is correct |
108 |
Correct |
292 ms |
57192 KB |
Output is correct |
109 |
Correct |
275 ms |
57108 KB |
Output is correct |
110 |
Correct |
325 ms |
65396 KB |
Output is correct |
111 |
Correct |
313 ms |
65336 KB |
Output is correct |