95分求调

#include<bits/stdc++.h>
using namespace std;
int n,L,a[100010],l=0,r,ans,ansl,ansr;
int f1(int mid) {
	if(a[ansl]==mid) {
		int left=1,right=n;
		while(left<right) {
			int Mid=(left+right)/2;
			if(Mid<=ansl-1&&Mid>=ansl-L) {
				if(a[Mid]<mid-1) {
					left=Mid+1;
				} else {
					right=Mid;
				}
			} else {
				if(a[Mid]<mid) {
					left=Mid+1;
				} else {
					right=Mid;
				}
			}
		}
		if((n-left+1)>=mid) {
			return 1;
		} else {
			return 0;
		}
	} else {
		int left=1,right=n;
		while(left<right) {
			int Mid=(left+right)/2;
			if(Mid<=ansl&&Mid>=ansl-L+1) {
				if(a[Mid]<mid-1) {
					left=Mid+1;
				} else {
					right=Mid;
				}
			} else {
				if(a[Mid]<mid) {
					left=Mid+1;
				} else {
					right=Mid;
				}
			}
		}
		if((n-left+1)>=mid) {
			return 1;
		} else {
			return 0;
		}
	}
}
int f2(int midd) {
	int le=1,ri=n;
	ansl=0,ansr=0;
	while(le<ri) {
		int mid=(le+ri+1)/2;
		if(a[mid]<=midd) {
			le=mid;
		} else {
			ri=mid-1;
		}
		ansl=le,ansr=ri;
	}
	return 0;
}
main() {
	cin>>n>>L;
	r=n+1;
	for(int i=1; i<=n; i++) {
		cin>>a[i];
	}
	sort(a+1,a+n+1);
	while(l<r) {
		int m=(l+r+1)/2;
		f2(m);
		if(f1(m)==1) {
			l=m,ans=m;
		} else {
			r=m-1;
		}
	}
	cout<<ans;
}