#include<bits/stdc++.h>
#define pb push_back
#define int long long
#define vi vector<int>
#define vvi vector<vector<int>>
#define pii pair<int, int>
#define vpii vector<pair<int, int>>
#define vc vector<char>
#define vb vector<bool>
#define mii map<int,int>
#define f0r(i,n) for(int i=0;i<n;i++)
#define FOR(i,k,n) for(int i=k;i<n;i++)
#define all(v) (v).begin(),(v).end()
#define rall(v) (v).rbegin(),(v).rend()
#define in(a) int a; cin>>a
#define in2(a,b) int a,b; cin>>a>>b
#define in3(a,b,c) int a,b,c; cin>>a>>b>>c
#define in4(a,b,c,d) int a,b,c,d; cin>>a>>b>>c>>d
#define vin(v,n); vi v(n); f0r(i,n){cin>>v[i];}
#define out(a) cout<<a<<'\n'
#define out2(a,b) cout<<a<<' '<<b<<'\n'
#define out3(a,b,c) cout<<a<<' '<<b<<' '<<c<<'\n'
#define out4(a,b,c,d) cout<<a<<' '<<b<<' '<<c<<' '<<d<<'\n'
#define vout(v) for(auto u : v){cout<<u<<' ';} cout<<'\n'
#define dout(a) cout<<a<<' '<<#a<<'\n'
#define dout2(a,b) cout<<a<<' '<<#a<<' '<<b<<' '<<#b<<'\n'
#define yn(x); if(x){cout<<"YES"<<'\n';}else{cout<<"NO"<<'\n';}
const int leg = 1e9 + 7;
const int mod = 998244353;
using namespace std;
signed main(){
ios::sync_with_stdio(false);
cin.tie(NULL);
//ifstream cin(".in");
//ofstream cout(".out");
in2(n,m);
vpii v;
f0r(i,n){
in2(a,b);
v.pb({a,b});
}
sort(all(v));
vpii w;
int mx = -1;
f0r(i, n){
if(v[i].second + (v[i].first > v[i].second) * m > mx){
w.pb(v[i]);
mx = v[i].second + (v[i].first > v[i].second) * m;
}
}
n = w.size();
f0r(i,n){
if(w[i].first > w[i].second)w[i].second += m;
}
f0r(i,n){
w.pb({w[i].first + m, w[i].second + m});
}
/*
f0r(i, n){
out2(w[i].first, w[i].second);
}
*/
int ptr = 0;
vi nxt(n*2);
f0r(i, n*2){
while(w[i].first <= w[ptr].first && w[ptr].first <= w[i].second){
ptr++;
ptr %= 2 * n;
}
if(ptr != 0)nxt[i] = ptr - 1;
else nxt[i] = 2 * n-1;
}
//vout(nxt);
int jmp[n*2][20];
f0r(i, n*2){
jmp[i][0] = nxt[i];
}
FOR(i, 1, 20){
f0r(j,n*2){
jmp[j][i] = jmp[jmp[j][i-1]][i-1];
}
}
f0r(i, n){
//out2(jmp[i][0].first, jmp[i][0].second);
}
//out("");
f0r(i, n){
//out2(jmp[i][4].first, jmp[i][4].second);
}
int ans = 4e18;
f0r(i, n){
if(jmp[i][0] >= i + n){
ans = min(ans, 2ll);
}
else{
int cur = 0;
int dex = i;
for(int j = 19; j>=0; j--){
if(jmp[dex][j] < i + n){
cur += (1 << j);
dex = jmp[dex][j];
}
/*
if(loops == 0){
if(jmp[dex][j].second == 1 && w[jmp[dex][j].first].second < w[i].first){
cur += (1 << j);
loops++;
dex = jmp[dex][j].first;
//out("path 1");
}
else if(jmp[dex][j].second == 0){
cur += (1 << j);
dex = jmp[dex][j].first;
//out("path 2");
}
}
else if(loops == 1){
if(jmp[dex][j].second == 0 && w[jmp[dex][j].first].second < w[i].first){
cur += (1 << j);
dex = jmp[dex][j].first;
//out("path 3");
}
}
*/
//dout2(loops, dex);
}
//out(cur);
if(cur != (1 << 20) - 1)ans = min(ans, cur + 2);
}
}
if(ans != 4e18)out(ans);
else out(-1);
}
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
1 ms |
336 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
1 ms |
336 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
1 ms |
336 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
336 KB |
Output is correct |
| 2 |
Incorrect |
1 ms |
336 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
336 KB |
Output is correct |
| 2 |
Incorrect |
1 ms |
456 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
1 ms |
336 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
