#include <bits/stdc++.h>
#pragma GCC target("avx,avx2,fma")
#pragma GCC optimize("Ofast,unroll-loops")
using namespace std;
#define pb push_back
#define int long long
#define f first
#define s second
#define pii pair<int,int>
const int mod= 1e9 +7;
const int N=2505;
vector<vector<int>> dist(N, vector<int> (N, mod));
void solve(){
int n,m,k;
cin>>n;
if(n<=2505){
vector<int>l(n+1),r(n+1);
for(int i = 0;i<n;i++){
int a,b;
cin>>l[i]>>r[i];
l[i]--;r[i]--;
}
int h,x;
cin>>h>>x;
x--;
priority_queue <pair<int,pii>, vector <pair<int,pii>>, greater <pair<int,pii>> > q;
q.push({1,{l[x],r[x]}});
dist[l[x]][r[x]] = 1;
int ml = -1,mr = -1;
while(!q.empty()){
auto [w,t] = q.top();
int x = t.f,y = t.s;
q.pop();
if(dist[x][y]<w)continue;
int ml = x;int mr = y;
for(int i = x;i<=y;i++){
ml = min(ml,l[i]);
mr = max(mr,r[i]);
if(l[i]<x&&r[i]>y&&dist[l[i]][r[i]]>dist[x][y]+1){
dist[l[i]][r[i]] = dist[x][y] + 1;
q.push({dist[l[i]][r[i]],{l[i],r[i]}});
}
}
if(x<y){
if(dist[ml][y]>dist[x][y] + 1){
dist[ml][y] = dist[x][y] + 1;
q.push({dist[ml][y],{ml,y}});
}
if(dist[x][mr]>dist[x][y] + 1){
dist[x][mr] = dist[x][y] + 1;
q.push({dist[x][mr],{x,mr}});
}
if(dist[x+1][y-1]>dist[x][y]){
dist[x+1][y-1] = dist[x][y];
q.push({dist[x+1][y-1],{x+1,y-1}});
}
// dist[x][mr] = dist[x][y] + 1;
}
else if(x==y){
if(dist[l[x]][r[x]]>dist[x][y] + 1){
dist[l[x]][r[x]] = dist[x][y] + 1;
q.push({dist[l[x]][r[x]],{l[x],r[x]}});
}
}
}
if(dist[0][n-1]==mod)cout<<-1<<"\n";
else cout<<dist[0][n-1]<<"\n";
}
else{
vector<pii>v;vector<int>pref(n+1,0);
int r1 = 1;
int cnt = 1;
for(int i = 0;i<n;i++){
int l,r;
cin>>l>>r;
v.pb({l,r});
if(i==0)r1 = r;
if(i==n)cout<<"Baiysh want a rulet!!!!!!!!!!!!!!!!!!!!!!\n";
else{
pref[i+1] = max(pref[i],r);
}
}
int last = -1;int ans = 1;
while(r1!=n){
last = r1;
r1 = pref[r1];
ans++;
if(last==r1){
cout<<-1<<"\n";
exit(0);
}
}
cout<<ans<<"\n";
}
}
signed main()
{
// freopen("seq.in", "r", stdin);
// freopen("seq.out", "w", stdout);
ios_base::sync_with_stdio(0);cin.tie(NULL);cout.tie(NULL);
int cnt=0;
int tt=1;
while(tt--)solve();
}
Compilation message
passport.cpp: In function 'void solve()':
passport.cpp:24:8: warning: unused variable 'a' [-Wunused-variable]
24 | int a,b;
| ^
passport.cpp:24:10: warning: unused variable 'b' [-Wunused-variable]
24 | int a,b;
| ^
passport.cpp:37:7: warning: unused variable 'ml' [-Wunused-variable]
37 | int ml = -1,mr = -1;
| ^~
passport.cpp:37:15: warning: unused variable 'mr' [-Wunused-variable]
37 | int ml = -1,mr = -1;
| ^~
passport.cpp:86:6: warning: unused variable 'cnt' [-Wunused-variable]
86 | int cnt = 1;
| ^~~
passport.cpp:16:8: warning: unused variable 'm' [-Wunused-variable]
16 | int n,m,k;
| ^
passport.cpp:16:10: warning: unused variable 'k' [-Wunused-variable]
16 | int n,m,k;
| ^
passport.cpp: In function 'int main()':
passport.cpp:123:6: warning: unused variable 'cnt' [-Wunused-variable]
123 | int cnt=0;
| ^~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
24 ms |
49496 KB |
Output is correct |
2 |
Correct |
24 ms |
49492 KB |
Output is correct |
3 |
Correct |
23 ms |
49496 KB |
Output is correct |
4 |
Correct |
57 ms |
56332 KB |
Output is correct |
5 |
Correct |
50 ms |
55628 KB |
Output is correct |
6 |
Correct |
50 ms |
56012 KB |
Output is correct |
7 |
Correct |
47 ms |
57216 KB |
Output is correct |
8 |
Correct |
43 ms |
56012 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
23 ms |
49500 KB |
Output is correct |
2 |
Correct |
23 ms |
49500 KB |
Output is correct |
3 |
Correct |
24 ms |
49500 KB |
Output is correct |
4 |
Correct |
24 ms |
49444 KB |
Output is correct |
5 |
Correct |
23 ms |
49500 KB |
Output is correct |
6 |
Correct |
23 ms |
49572 KB |
Output is correct |
7 |
Correct |
24 ms |
49500 KB |
Output is correct |
8 |
Correct |
24 ms |
49496 KB |
Output is correct |
9 |
Correct |
24 ms |
49492 KB |
Output is correct |
10 |
Correct |
26 ms |
49640 KB |
Output is correct |
11 |
Correct |
65 ms |
49500 KB |
Output is correct |
12 |
Correct |
58 ms |
49496 KB |
Output is correct |
13 |
Correct |
64 ms |
49632 KB |
Output is correct |
14 |
Correct |
55 ms |
49496 KB |
Output is correct |
15 |
Correct |
62 ms |
49500 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
23 ms |
49500 KB |
Output is correct |
2 |
Correct |
23 ms |
49500 KB |
Output is correct |
3 |
Correct |
24 ms |
49500 KB |
Output is correct |
4 |
Correct |
24 ms |
49444 KB |
Output is correct |
5 |
Correct |
23 ms |
49500 KB |
Output is correct |
6 |
Correct |
23 ms |
49572 KB |
Output is correct |
7 |
Correct |
24 ms |
49500 KB |
Output is correct |
8 |
Correct |
24 ms |
49496 KB |
Output is correct |
9 |
Correct |
24 ms |
49492 KB |
Output is correct |
10 |
Correct |
26 ms |
49640 KB |
Output is correct |
11 |
Correct |
65 ms |
49500 KB |
Output is correct |
12 |
Correct |
58 ms |
49496 KB |
Output is correct |
13 |
Correct |
64 ms |
49632 KB |
Output is correct |
14 |
Correct |
55 ms |
49496 KB |
Output is correct |
15 |
Correct |
62 ms |
49500 KB |
Output is correct |
16 |
Execution timed out |
2076 ms |
49984 KB |
Time limit exceeded |
17 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
23 ms |
49500 KB |
Output is correct |
2 |
Correct |
23 ms |
49500 KB |
Output is correct |
3 |
Correct |
24 ms |
49500 KB |
Output is correct |
4 |
Correct |
24 ms |
49444 KB |
Output is correct |
5 |
Correct |
23 ms |
49500 KB |
Output is correct |
6 |
Correct |
23 ms |
49572 KB |
Output is correct |
7 |
Correct |
24 ms |
49500 KB |
Output is correct |
8 |
Correct |
24 ms |
49496 KB |
Output is correct |
9 |
Correct |
24 ms |
49492 KB |
Output is correct |
10 |
Correct |
26 ms |
49640 KB |
Output is correct |
11 |
Correct |
65 ms |
49500 KB |
Output is correct |
12 |
Correct |
58 ms |
49496 KB |
Output is correct |
13 |
Correct |
64 ms |
49632 KB |
Output is correct |
14 |
Correct |
55 ms |
49496 KB |
Output is correct |
15 |
Correct |
62 ms |
49500 KB |
Output is correct |
16 |
Execution timed out |
2076 ms |
49984 KB |
Time limit exceeded |
17 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
24 ms |
49496 KB |
Output is correct |
2 |
Correct |
24 ms |
49492 KB |
Output is correct |
3 |
Correct |
23 ms |
49496 KB |
Output is correct |
4 |
Correct |
57 ms |
56332 KB |
Output is correct |
5 |
Correct |
50 ms |
55628 KB |
Output is correct |
6 |
Correct |
50 ms |
56012 KB |
Output is correct |
7 |
Correct |
47 ms |
57216 KB |
Output is correct |
8 |
Correct |
43 ms |
56012 KB |
Output is correct |
9 |
Correct |
23 ms |
49500 KB |
Output is correct |
10 |
Correct |
23 ms |
49500 KB |
Output is correct |
11 |
Correct |
24 ms |
49500 KB |
Output is correct |
12 |
Correct |
24 ms |
49444 KB |
Output is correct |
13 |
Correct |
23 ms |
49500 KB |
Output is correct |
14 |
Correct |
23 ms |
49572 KB |
Output is correct |
15 |
Correct |
24 ms |
49500 KB |
Output is correct |
16 |
Correct |
24 ms |
49496 KB |
Output is correct |
17 |
Correct |
24 ms |
49492 KB |
Output is correct |
18 |
Correct |
26 ms |
49640 KB |
Output is correct |
19 |
Correct |
65 ms |
49500 KB |
Output is correct |
20 |
Correct |
58 ms |
49496 KB |
Output is correct |
21 |
Correct |
64 ms |
49632 KB |
Output is correct |
22 |
Correct |
55 ms |
49496 KB |
Output is correct |
23 |
Correct |
62 ms |
49500 KB |
Output is correct |
24 |
Execution timed out |
2076 ms |
49984 KB |
Time limit exceeded |
25 |
Halted |
0 ms |
0 KB |
- |