D. Jumping Through Segments

  输入数据

4
5
1 5
3 4
5 6
8 10
0 1
3
0 2
0 1
0 3
3
3 8
10 18
6 11
4
10 20
0 5
15 17
2 2 

输出范围 

7
0
5
13

 

#include<bits/stdc++.h>
#define int long long 
using namespace std;
typedef pair<char,int>PII;
const int N=2e5+10;
int l[N],r[N];
int n;
bool check(int k)
{
	int L=0,R=0;
	for(int i=1;i<=n;i++)
	{
		int LL=L-k,RR=R+k;
		if(LL>r[i]||RR<l[i]) return false;
		L=max(LL,l[i]);
		R=min(RR,r[i]);
	}
	return true;
}
signed main()
{
	int t;cin>>t;
	while(t--)
	{
		cin>>n;
		for(int i=1;i<=n;i++) cin>>l[i]>>r[i];
		int l=0,r=1e9+10;
		while(l<r)
		{
			int mid=(l+r)>>1;
			if(check(mid)) r=mid;
			else l=mid+1;
		}
		cout<<l<<endl;
	}
	return 0;
}