hdu4190 二分答案

/*二分答案即可*/
#include<bits/stdc++.h>
#define maxn 500005
#define ll long long
#define INF 5000005

using namespace std;

ll n,b,a[maxn];

int judge(ll x){
    ll tot=;
    for(int i=;i<=n;i++)
        tot+=a[i]/x+(a[i]%x!=);
    if(tot<=b) return ;
    else return ;
}

int main(){
    while(scanf("%lld%lld",&n,&b),n>){
        ll l=,r=INF,mid,ans;
        for(int i=;i<=n;i++) scanf("%lld",&a[i]);
        while(l<=r){
            mid=l+r>>;
            if(judge(mid))//要用的盒子小于b个
                ans=mid,r=mid-;
            else
                l=mid+;
        }
        printf("%lld\n",ans);
    }
    return ;
}