最大化最小值,二分答案
#include<cstdio>
#include<algorithm>
#include<iostream>
#include<cmath>
#define ll long long
using namespace std;
const int N = 3e5+9;
const int inf = 0x3f3f3f3f;
int a[N];
int n;
int work(int mid)
{
ll o1=0,o2=0;
for(int i = 0; i<n; i++){
if(a[i]<mid) o1 += mid-a[i];
else if(a[i]>mid) o2 += (a[i]-mid)/2;
}
if(o1<=o2) return 1;
else return 0;
}
int main()
{
// freopen("in.txt","r",stdin);
ios::sync_with_stdio(false);
int t; cin>>t;
while(t--){
cin>>n;
int minn=inf,maxx = -inf;
for(int i = 0; i<n; i++) {
cin>>a[i];
minn=min(minn,a[i]);
maxx = max(maxx,a[i]);
}
int l = 0,r = maxx;
while(l<r){
int mid = (l+r+1)>>1;
if(work(mid)) l=mid;
else r = mid-1;
}
cout<<l<<endl;
}
return 0;
}