清北刷题冲刺 10-31 a.m

#include<iostream>
#include<cstdio>
#include<algorithm>
using namespace std;
int n,a[1000010],cnt;
int main(){
    freopen("multiset.in","r",stdin);freopen("multiset.out","w",stdout);
//    freopen("Cola.txt","r",stdin);
    scanf("%d",&n);
    for(int i=1;i<=n;i++)scanf("%d",&a[i]);
    if(n==1&&a[1]==0){
        puts("0");
        return 0;
    }
    int ans=0;
    sort(a+1,a+n+1);
    int q=1;
    for(int i=1;i<=n;i++){
        if(a[i]!=0){q=i;break;}
        cnt++;
    }
    while(1){
        if(q>n)break;
        ans++;cnt=cnt/2+cnt%2;
        for(int i=q;i<=n;i++)a[i]-=1;
//        for(int i=1;i<=n;i++)cout<<a[i]<<‘ ‘;
        while(a[q]==0&&q<=n)cnt++,q++;
    }
    while(cnt>1){
        ans++;
        cnt=cnt/2+cnt%2;
    }
    printf("%d",ans);
}