I have a exception thrown at 0x00007ff75b5f24f1 in nmexam2.exe: 0xc0000005: access violation reading location 0x0000000000000001 problem. I cant figure out why that is the case

#include <iostream>
using namespace std;

enum
{
  Items = 30, // use a symbolic name, instead of a number
};


//float compute_avewil(const int low_value[30], const int high_value[30])

// pass the output parameter 'average_value' explicitely. Make the return value 'void', this function always succeds
void compute_avewil(const int low_value[], const int high_value[], float average_value[])
{
    for(int i=0;i<Items;i++) //loop to add and divide indices
    {
        average_value[i] = low_value[i] + high_value[i];
        average_value[i] = average_value[i] / 2;
    }
    // do not output anything here, keep computations and output seperated
}

int find_highthat(float average_value[])
{
    int maxex = 0;
    float max = average_value[maxex];

    for(int i=1;i<Items;++i)
    {
        if(max<average_value[i])
        {
            maxex = i;
            max = average_value[i];
        }
    }
    // do not output anything here, ...
    return maxex;
}

//int main(float average_value[30])
int main() // main has a fixed signature, either 'int main()' or 'int main(int argc, char * argv[])'
{
    //What's the purpose of this?  int id_number[30] = { 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30 };
    int high_value[Items] = { 10,20,30,40,50,60,70,80,90,100,110,120,130,140,150,160,170,180,190,200,210,220,230,240,250,260,270,280,290,300 };
    int low_value[Items] = { 1,2,3,4,5,6,7,8,9,10,9,8,7,6,5,4,3,2,1,0,1,2,3,4,5,4,3,2,1,0 };
    float average_value[Items]; // create the array used for results


    compute_avewil(low_value, high_value, average_value); // compute the averages

    // show the average
    cout << "averages: ";
    for(int i=0;i<Items;i++)
    {
        cout << average_value[i] << " ";
    }
    cout << endl;


    int maxex = find_highthat(average_value); // find the maximum of the averages

    // show the maximum of the averages
    cout << "maximum of averages: average_value[" << maxex << "] = " << average_value[maxex] << endl;
}

#include <algorithm>
#include <array>
#include <vector>

using namespace std;

using Value = array<int, 2>; // first item of the array is 'high', second item is 'Low'
using Values = vector<Value>; // the collection of 'high' and 'low' 

double avg(const Value & v) // computes the average
{
  return (v[0] + v[1]) / 2.0;
}


int main()
{ //                 high,low   high,low   high,low   high,low
  Values values = { { 10, 1 }, { 20, 2 }, { 30, 3 }, { 40, 4 } /*, {50,5} and so on.. */ };

  vector <double> averages;

  for (auto const & v : values)
    averages.push_back(avg(v));


  cout << "averages ";
  for (auto a : averages)
    cout << a << " ";
  cout << endl;

  auto itamax = max_element(averages.begin(), averages.end());
  auto amax_index = distance(averages.begin(), itamax);
  cout << "max of averages: averages[" << amax_index << "] = " << (*itamax) << endl;
}