题解：CF2005B2 The Strict Teacher (Hard Version)

#include<bits/stdc++.h>
using namespace std;
int T,n,m,q,b[100001],a,l,r,lef,rig,mid,ans;
int main(){
	scanf("%d",&T);//注意有多组数据
	while(T --){
		scanf("%d%d%d",&n,&m,&q);
		for(int i = 1;i <= m;i ++){
			scanf("%d",&b[i]);
		}
		sort(b + 1,b + m + 1);
		for(int i = 1;i <= q;i ++){
			scanf("%d",&a);
			l = 0,r = m;
			while(l < r){//二分查找
				mid = l + r + 1 >> 1;
				if(b[mid] < a){
					l = mid;
				}
				else{
					r = mid - 1;
				}
			}
			if(!l){
				ans = b[1] - 1;
			}
			else if(l == m){
				ans = n - b[m];
			}
			else{
				lef = b[l];
				rig = b[l + 1];
				if((rig - lef) % 2 == 1){
					ans = (rig - lef - 1) / 2; 
				}
				else{
					ans = (rig - (rig + lef >> 1));
				}
			}
			printf("%d\n",ans);
		}
	}
	return 0;
}