C++ Vector understanding - vector

Question

I am currently using codewars.com to practice my coding skills. I finished one of the problems and wanted to check what other people's solutions were and I found one I couldn't understand. It's much better than my solution and I would like to understand it more. such what does "*std" do exactly. what is the +=i doing to the min_elements and what is happening to the min elements?
long queueTime(std::vector<int> customers,int n){
std::vector<long> queues(n, 0);
for (int i : customers)
*std::min_element(queues.begin(), queues.end()) += i;
return *std::max_element(queues.cbegin(), queues.cend());
}
This was my solution:
#include <iostream>
#include <vector>
#include <array>
using namespace std;
long queueTime(std::vector<int> customers,int n){
int i = 0; //start of Queue
int count = 0; //keeps track of how many items has been
processed
int biggest = 0; //Last/largest ending item size, add to count at end
int list [n]; //Declared number of registers by size n
for(int k = 0;k<n;k++) //sets each existing register to have 0
items
{
list[k] = 0;
}
//Start of processing customers, ends when last customer is at register.
for (auto i = customers.begin(); i!=customers.end();)
{
//checks if there are free registers.
for(int index = 0; index<n && i!=customers.end();index++)
{
if(list[index]==0)
{
list[index] = *i;
i++;
}
}
//Subtract 1 from every register
int temp=0;
for (int k =0;k<n;k++)
{
if(list[k]!= 0)
{
temp = list[k];
temp = temp-1;
list[k] = temp;
}
}
//increase count of items processed
count++;
}
//calculates the largest number of items a customer has amungst the last few
customers.
for(int j=0;j<n;j++)
{
if(list[j]>biggest)
{
biggest = list[j];
}
}
//end first part
cout<<"\nCount: "<<count<<" Biggest: "<<biggest<<endl;
cout<<"End Function:"
<<"\n************************\n***************************
*******************\n"<<endl;
//answer if number of items processed + last biggest number of items.
return count+biggest;
}

Answer 1

The code is mapping a set of integers to n buckets and minimizing the sum of the elements assigned to a given bucket.
For each customer int i , the smallest element of the queue is incremented by i. Then the largest resulting queue value is returned.
std::vector is a qualified name lookup of an identifier within the std namespace.
min_element returns an iterator. The dereference operator (*) produces an lvalue that is incremented by a compound assignment operator (+=).