#include<bits/stdc++.h>
#ifdef LOCAL
#include "Essentials/algo/debug.h"
#else
#define debug(...) 69
#define debugArr(...) 69
#endif
using namespace std;
typedef long long ll;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
const int N = 4e5 + 23;
const int LOG = 20;
const ll inf = 1e18;
#define F first
#define S second
#define pb push_back
#define kill(x) cout<<x<<endl, exit(0);
#define all(x) x.begin(),x.end()
#define sz(x) (int)x.size()
#define lc (v << 1)
#define rc ((v<<1) |1)
int n,m;
vector<pii> edges;
int up[LOG][N];
int32_t main() {
cin.tie(nullptr)->sync_with_stdio(false);
cin>>n>>m;
for(int i = 1; i <= n ; i ++) {
int l,r; cin>>l>>r;
if(l <= r) {
edges.pb({l,r});
edges.pb({l+m,r+m});
} else {
edges.pb({l,r+m});
}
}
sort(all(edges));
set<pii> st;
int R = sz(edges)-1;
for(int i = sz(edges)-1; i >= 0; i --) {
while(R > i && edges[R].F > edges[i].S) {
st.erase({edges[R].S,R});
R --;
}
if(sz(st)) up[0][i] = st.rbegin()->S;
else up[0][i] = i;
for(int j = 1; j < LOG; j ++) up[j][i] = up[j-1][up[j-1][i]];
st.insert({edges[i].S,i});
}
int ans = N + 23;
for(int i = 0;i < sz(edges); i ++) {
int l = edges[i].F;
if(edges[up[LOG-1][i]].S - l < m) continue;
int mn = 1,v= i;
for(int j = LOG-1; j >= 0 ; j --) {
if(edges[up[j][v]].S - l < m) {
mn += (1 << j);
v = up[j][i];
}
}
ans= min(ans,mn + 1);
}
cout<<(ans == N+ 23 ? -1 : ans) << '\n';
return 0;
}
// Jumpsuit, Jumpsuit cover me!
// Jumpsuit, Jumpsuit cover me!
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
344 KB |
Output is correct |
2 |
Correct |
0 ms |
604 KB |
Output is correct |
3 |
Incorrect |
0 ms |
604 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
344 KB |
Output is correct |
2 |
Correct |
0 ms |
604 KB |
Output is correct |
3 |
Incorrect |
0 ms |
604 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
344 KB |
Output is correct |
2 |
Correct |
0 ms |
604 KB |
Output is correct |
3 |
Incorrect |
0 ms |
604 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Correct |
0 ms |
604 KB |
Output is correct |
3 |
Incorrect |
0 ms |
348 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
344 KB |
Output is correct |
2 |
Correct |
0 ms |
604 KB |
Output is correct |
3 |
Correct |
0 ms |
604 KB |
Output is correct |
4 |
Correct |
1 ms |
348 KB |
Output is correct |
5 |
Correct |
0 ms |
348 KB |
Output is correct |
6 |
Correct |
0 ms |
348 KB |
Output is correct |
7 |
Correct |
0 ms |
604 KB |
Output is correct |
8 |
Incorrect |
0 ms |
604 KB |
Output isn't correct |
9 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
344 KB |
Output is correct |
2 |
Correct |
0 ms |
604 KB |
Output is correct |
3 |
Incorrect |
0 ms |
604 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |