#include<bits/stdc++.h>
#define ff first
#define ss second
#define all(x) x.begin(), x.end()
using namespace std;
using ll = long long;
using pii = pair<int,int>;
using pll = pair<ll,ll>;
template<typename T>
using matrix = vector<vector<T>>;
const int INF = 1<<30;
int main() {
cin.tie(0)->sync_with_stdio(0);
int n, q;
cin >> n >> q;
vector<pii> v(n);
for(pii& i : v){
cin >> i.ff >> i.ss;
i.ff = INF-i.ff;
i.ss = INF-i.ss;
swap(i.ff,i.ss);
}
// cout << "----------\n";
// for(pii i : v)
// cout << i.ff << ' ' << i.ss << '\n';
// cout << "----------\n";
vector<int>o(n);
iota(all(o),0);
sort(all(o),[&](int a, int b){
return v[a] > v[b];
});
vector<int> jmp(n);
vector<int> st;
for(int i : o){
int ini = 0, fim = st.size();
while(ini!=fim){
int m = (ini+fim)>>1;
if(v[st[m]].ff <= v[i].ss)
fim = m;
else ini = m+1;
}
if(ini == st.size()){
jmp[i] = i;
} else jmp[i] = st[ini];
while(!st.empty() && v[st.back()].ss <= v[i].ss)
st.pop_back();
if(st.empty() || v[st.back()].ff > v[i].ff)
st.push_back(i);
// cout << i << ":\n";
// for(int i : st)
// cout << i << ' ';
// cout << '\n';
}
matrix<int> lift(20,vector<int>(n));
for(int i = 0; i < n; i++){
lift[0][i] = jmp[i];
// cout << jmp[i] << ' ';
}
// cout << '\n';
for(int i = 1; i < 20; i++){
for(int j = 0; j < n; j++){
lift[i][j] = lift[i-1][lift[i-1][j]];
}
}
while(q--){
int a, b;
cin >> a >> b;
a--, b--;
swap(a,b);
if(v[a].ff > v[b].ff){
cout << "impossible\n";
continue;
}
if(a==b){
cout << 0 << '\n';
continue;
}
if(v[a].ss >= v[b].ff){
cout << 1 << '\n';
continue;
}
int ct = 2;
for(int i = 19; i >= 0; i--){
if(v[lift[i][a]].ss < v[b].ff)
ct+=1<<i, a = lift[i][a];
}
a = lift[0][a];
if(v[a].ss >= v[b].ff){
cout << ct << '\n';
} else {
cout << "impossible\n";
}
}
}
Compilation message
events.cpp: In function 'int main()':
events.cpp:46:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
46 | if(ini == st.size()){
| ~~~~^~~~~~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
212 KB |
Output is correct |
2 |
Correct |
62 ms |
10824 KB |
Output is correct |
3 |
Correct |
78 ms |
10772 KB |
Output is correct |
4 |
Correct |
129 ms |
10844 KB |
Output is correct |
5 |
Correct |
84 ms |
10796 KB |
Output is correct |
6 |
Correct |
93 ms |
10948 KB |
Output is correct |
7 |
Correct |
84 ms |
10768 KB |
Output is correct |
8 |
Correct |
99 ms |
11360 KB |
Output is correct |
9 |
Correct |
95 ms |
11372 KB |
Output is correct |
10 |
Correct |
99 ms |
11300 KB |
Output is correct |
11 |
Correct |
86 ms |
11024 KB |
Output is correct |
12 |
Correct |
56 ms |
11076 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
212 KB |
Output is correct |
2 |
Correct |
0 ms |
212 KB |
Output is correct |
3 |
Correct |
1 ms |
340 KB |
Output is correct |
4 |
Correct |
1 ms |
340 KB |
Output is correct |
5 |
Correct |
1 ms |
340 KB |
Output is correct |
6 |
Correct |
1 ms |
340 KB |
Output is correct |
7 |
Correct |
1 ms |
340 KB |
Output is correct |
8 |
Correct |
1 ms |
340 KB |
Output is correct |
9 |
Correct |
1 ms |
340 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
212 KB |
Output is correct |
2 |
Correct |
0 ms |
212 KB |
Output is correct |
3 |
Correct |
1 ms |
340 KB |
Output is correct |
4 |
Correct |
1 ms |
340 KB |
Output is correct |
5 |
Correct |
1 ms |
340 KB |
Output is correct |
6 |
Correct |
1 ms |
340 KB |
Output is correct |
7 |
Correct |
1 ms |
340 KB |
Output is correct |
8 |
Correct |
1 ms |
340 KB |
Output is correct |
9 |
Correct |
1 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 |
1 ms |
340 KB |
Output is correct |
13 |
Correct |
1 ms |
340 KB |
Output is correct |
14 |
Correct |
1 ms |
340 KB |
Output is correct |
15 |
Correct |
1 ms |
340 KB |
Output is correct |
16 |
Correct |
1 ms |
340 KB |
Output is correct |
17 |
Correct |
1 ms |
340 KB |
Output is correct |
18 |
Correct |
1 ms |
340 KB |
Output is correct |
19 |
Correct |
31 ms |
1292 KB |
Output is correct |
20 |
Correct |
27 ms |
1224 KB |
Output is correct |
21 |
Correct |
30 ms |
1484 KB |
Output is correct |
22 |
Correct |
25 ms |
1720 KB |
Output is correct |
23 |
Correct |
22 ms |
1364 KB |
Output is correct |
24 |
Correct |
21 ms |
1440 KB |
Output is correct |
25 |
Correct |
32 ms |
1208 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
212 KB |
Output is correct |
2 |
Correct |
0 ms |
212 KB |
Output is correct |
3 |
Correct |
1 ms |
340 KB |
Output is correct |
4 |
Correct |
1 ms |
340 KB |
Output is correct |
5 |
Correct |
1 ms |
340 KB |
Output is correct |
6 |
Correct |
1 ms |
340 KB |
Output is correct |
7 |
Correct |
1 ms |
340 KB |
Output is correct |
8 |
Correct |
1 ms |
340 KB |
Output is correct |
9 |
Correct |
1 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 |
1 ms |
340 KB |
Output is correct |
13 |
Correct |
1 ms |
340 KB |
Output is correct |
14 |
Correct |
1 ms |
340 KB |
Output is correct |
15 |
Correct |
1 ms |
340 KB |
Output is correct |
16 |
Correct |
1 ms |
340 KB |
Output is correct |
17 |
Correct |
1 ms |
340 KB |
Output is correct |
18 |
Correct |
1 ms |
340 KB |
Output is correct |
19 |
Correct |
38 ms |
10580 KB |
Output is correct |
20 |
Correct |
33 ms |
10580 KB |
Output is correct |
21 |
Correct |
40 ms |
10052 KB |
Output is correct |
22 |
Correct |
37 ms |
10480 KB |
Output is correct |
23 |
Correct |
36 ms |
10572 KB |
Output is correct |
24 |
Correct |
55 ms |
10632 KB |
Output is correct |
25 |
Correct |
24 ms |
10088 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
78 ms |
10824 KB |
Output is correct |
2 |
Correct |
77 ms |
10824 KB |
Output is correct |
3 |
Correct |
119 ms |
10852 KB |
Output is correct |
4 |
Correct |
92 ms |
11288 KB |
Output is correct |
5 |
Correct |
102 ms |
11200 KB |
Output is correct |
6 |
Correct |
82 ms |
10956 KB |
Output is correct |
7 |
Correct |
113 ms |
10976 KB |
Output is correct |
8 |
Correct |
109 ms |
11060 KB |
Output is correct |
9 |
Correct |
40 ms |
10572 KB |
Output is correct |
10 |
Correct |
109 ms |
10596 KB |
Output is correct |
11 |
Correct |
74 ms |
10588 KB |
Output is correct |
12 |
Correct |
86 ms |
10568 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
212 KB |
Output is correct |
2 |
Correct |
62 ms |
10824 KB |
Output is correct |
3 |
Correct |
78 ms |
10772 KB |
Output is correct |
4 |
Correct |
129 ms |
10844 KB |
Output is correct |
5 |
Correct |
84 ms |
10796 KB |
Output is correct |
6 |
Correct |
93 ms |
10948 KB |
Output is correct |
7 |
Correct |
84 ms |
10768 KB |
Output is correct |
8 |
Correct |
99 ms |
11360 KB |
Output is correct |
9 |
Correct |
95 ms |
11372 KB |
Output is correct |
10 |
Correct |
99 ms |
11300 KB |
Output is correct |
11 |
Correct |
86 ms |
11024 KB |
Output is correct |
12 |
Correct |
56 ms |
11076 KB |
Output is correct |
13 |
Correct |
0 ms |
212 KB |
Output is correct |
14 |
Correct |
0 ms |
212 KB |
Output is correct |
15 |
Correct |
1 ms |
340 KB |
Output is correct |
16 |
Correct |
1 ms |
340 KB |
Output is correct |
17 |
Correct |
1 ms |
340 KB |
Output is correct |
18 |
Correct |
1 ms |
340 KB |
Output is correct |
19 |
Correct |
1 ms |
340 KB |
Output is correct |
20 |
Correct |
1 ms |
340 KB |
Output is correct |
21 |
Correct |
1 ms |
340 KB |
Output is correct |
22 |
Correct |
0 ms |
212 KB |
Output is correct |
23 |
Correct |
0 ms |
212 KB |
Output is correct |
24 |
Correct |
1 ms |
340 KB |
Output is correct |
25 |
Correct |
1 ms |
340 KB |
Output is correct |
26 |
Correct |
1 ms |
340 KB |
Output is correct |
27 |
Correct |
1 ms |
340 KB |
Output is correct |
28 |
Correct |
1 ms |
340 KB |
Output is correct |
29 |
Correct |
1 ms |
340 KB |
Output is correct |
30 |
Correct |
1 ms |
340 KB |
Output is correct |
31 |
Correct |
31 ms |
1292 KB |
Output is correct |
32 |
Correct |
27 ms |
1224 KB |
Output is correct |
33 |
Correct |
30 ms |
1484 KB |
Output is correct |
34 |
Correct |
25 ms |
1720 KB |
Output is correct |
35 |
Correct |
22 ms |
1364 KB |
Output is correct |
36 |
Correct |
21 ms |
1440 KB |
Output is correct |
37 |
Correct |
32 ms |
1208 KB |
Output is correct |
38 |
Correct |
0 ms |
212 KB |
Output is correct |
39 |
Correct |
0 ms |
212 KB |
Output is correct |
40 |
Correct |
1 ms |
340 KB |
Output is correct |
41 |
Correct |
1 ms |
340 KB |
Output is correct |
42 |
Correct |
1 ms |
340 KB |
Output is correct |
43 |
Correct |
1 ms |
340 KB |
Output is correct |
44 |
Correct |
1 ms |
340 KB |
Output is correct |
45 |
Correct |
1 ms |
340 KB |
Output is correct |
46 |
Correct |
1 ms |
340 KB |
Output is correct |
47 |
Correct |
38 ms |
10580 KB |
Output is correct |
48 |
Correct |
33 ms |
10580 KB |
Output is correct |
49 |
Correct |
40 ms |
10052 KB |
Output is correct |
50 |
Correct |
37 ms |
10480 KB |
Output is correct |
51 |
Correct |
36 ms |
10572 KB |
Output is correct |
52 |
Correct |
55 ms |
10632 KB |
Output is correct |
53 |
Correct |
24 ms |
10088 KB |
Output is correct |
54 |
Correct |
78 ms |
10824 KB |
Output is correct |
55 |
Correct |
77 ms |
10824 KB |
Output is correct |
56 |
Correct |
119 ms |
10852 KB |
Output is correct |
57 |
Correct |
92 ms |
11288 KB |
Output is correct |
58 |
Correct |
102 ms |
11200 KB |
Output is correct |
59 |
Correct |
82 ms |
10956 KB |
Output is correct |
60 |
Correct |
113 ms |
10976 KB |
Output is correct |
61 |
Correct |
109 ms |
11060 KB |
Output is correct |
62 |
Correct |
40 ms |
10572 KB |
Output is correct |
63 |
Correct |
109 ms |
10596 KB |
Output is correct |
64 |
Correct |
74 ms |
10588 KB |
Output is correct |
65 |
Correct |
86 ms |
10568 KB |
Output is correct |
66 |
Correct |
0 ms |
212 KB |
Output is correct |
67 |
Correct |
69 ms |
13888 KB |
Output is correct |
68 |
Correct |
101 ms |
13856 KB |
Output is correct |
69 |
Correct |
151 ms |
13800 KB |
Output is correct |
70 |
Correct |
124 ms |
13856 KB |
Output is correct |
71 |
Correct |
107 ms |
13820 KB |
Output is correct |
72 |
Correct |
91 ms |
13868 KB |
Output is correct |
73 |
Correct |
101 ms |
14268 KB |
Output is correct |
74 |
Correct |
154 ms |
14376 KB |
Output is correct |
75 |
Correct |
91 ms |
14232 KB |
Output is correct |
76 |
Correct |
94 ms |
14088 KB |
Output is correct |
77 |
Correct |
59 ms |
13384 KB |
Output is correct |
78 |
Correct |
0 ms |
212 KB |
Output is correct |
79 |
Correct |
1 ms |
340 KB |
Output is correct |
80 |
Correct |
1 ms |
340 KB |
Output is correct |
81 |
Correct |
1 ms |
432 KB |
Output is correct |
82 |
Correct |
1 ms |
340 KB |
Output is correct |
83 |
Correct |
1 ms |
340 KB |
Output is correct |
84 |
Correct |
1 ms |
340 KB |
Output is correct |
85 |
Correct |
1 ms |
340 KB |
Output is correct |
86 |
Correct |
32 ms |
2280 KB |
Output is correct |
87 |
Correct |
38 ms |
2268 KB |
Output is correct |
88 |
Correct |
30 ms |
2504 KB |
Output is correct |
89 |
Correct |
25 ms |
2508 KB |
Output is correct |
90 |
Correct |
22 ms |
2428 KB |
Output is correct |
91 |
Correct |
21 ms |
2388 KB |
Output is correct |
92 |
Correct |
27 ms |
2120 KB |
Output is correct |
93 |
Correct |
38 ms |
12516 KB |
Output is correct |
94 |
Correct |
35 ms |
11708 KB |
Output is correct |
95 |
Correct |
38 ms |
11956 KB |
Output is correct |
96 |
Correct |
46 ms |
12408 KB |
Output is correct |
97 |
Correct |
37 ms |
12472 KB |
Output is correct |
98 |
Correct |
38 ms |
12572 KB |
Output is correct |
99 |
Correct |
26 ms |
11340 KB |
Output is correct |
100 |
Correct |
101 ms |
13976 KB |
Output is correct |
101 |
Correct |
82 ms |
13940 KB |
Output is correct |
102 |
Correct |
76 ms |
14068 KB |
Output is correct |
103 |
Correct |
78 ms |
13628 KB |
Output is correct |
104 |
Correct |
76 ms |
13252 KB |
Output is correct |
105 |
Correct |
76 ms |
13700 KB |
Output is correct |
106 |
Correct |
80 ms |
13252 KB |
Output is correct |
107 |
Correct |
97 ms |
13328 KB |
Output is correct |
108 |
Correct |
90 ms |
13496 KB |
Output is correct |
109 |
Correct |
75 ms |
13364 KB |
Output is correct |
110 |
Correct |
62 ms |
13404 KB |
Output is correct |
111 |
Correct |
61 ms |
13372 KB |
Output is correct |