def dealt(k, b):
lost = 0
for x in b:
if k <= x:
continue
else:
lost += k - x
if k * n - lost >= h:
return True
else:
return False
T = int(input())
for _ in range(T):
n, h = map(int, input().split())
a = list(map(int, input().split()))
b = []
for i in range(n-1):
b.append(a[i+1] - a[i])
low = 0
if h % n == 0:
low = h // n
else:
low = h // n + 1
high = h
while low <= high:
mid = (low + high) // 2
ans = dealt(mid, b)
ans_1 = dealt(mid-1, b)
if ans and not ans_1:
print(mid)
break
elif ans:
high = mid - 1
else:
low = mid + 1#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define IOS ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
#define endl "\n"
bool is_possible(vector<ll>& v,ll n,ll h){
ll ct = 0;
for(int i=1;i<v.size();i++){
ct += min(n,(v[i]-v[i-1]));
}
ct += n;
if(ct>=h) return true;
else return false;
}
void solve(){
ll n,h;
cin>>n>>h;
vector<ll> v(n);
for(ll i=0;i<n;i++) cin>>v[i];
ll lo = 1,hi = h,ans=h;
while(lo<=hi){
ll mid = (hi+lo)/2;
if(is_possible(v,mid,h)){
ans = min(mid,ans);
hi = mid-1;
}
else lo = mid+1;
}
cout<<ans<<endl;
}
int main()
{
IOS
//precomp();
ll t;
cin>>t;
while(t--) solve();
return 0;
}1093A - Dice Rolling | 1360B - Honest Coach |
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