Функция , Указатели , С++ , Задачка (среднее арифметическое все введенных чисел)

#include <iostream.h>
double srarifm (int n);
void main()
{
int n,b;
do{
cout<<"vvedite kol-vo vvodimyh chisel";
cin>>n;
cout<<"srar vseh chisel= "<<srarifm(n)<<endl;
cout<<"1-DA 2-NET"<<endl;
cin>>b;
}
while (b==1);
}
double srarifm (int n) {
int total=0;
int num;
double srar=0;
for(int i=1; i<=n; ++i) {
cout <<"vvedite chislo: ";
cin>>num;
total+=num;
}
srar=(double)total/n;
return srar;
}

#include <iostream.h>
 
double SR(int *begin, int *end) {
  int numberOfElements = end - begin;
  int sum = 0;
  while (begin != end) {
    sum += *begin++;
  }
  return (double)sum / numberOfElements;
}
 
void readSequenceAndPrintAverage(int n) {
  int *vector = new int[n];
  cout << "Please, enter " << n << " elements." << endl;
  for (int i = 0; i < n; ++i) {
    cout << "Vvidite chislo " << i << ": ";
    cin >> vector[i];
  }
  cout << "SREDNEE ARIFMETICHESKOE " << SR(vector, vector + n) << endl;
  delete [] vector;
}
 
int main(int argc, char **argv) {
  readSequenceAndPrintAverage(3);
 
  
  return 0;
}

// . . .
cin>> n;
int *vector = new int[n];
// . . .

int accumulate(int* first,int* last)
{
   int sum=0;
   for(; first!=last; ++first) sum+= *first;
   return sum;
}
 
int main()
{
    int size=0;
    cin>> size;
 
    int* A= new int[size];
 
    for(int i=0; i<size; i++) cin>>A[i];
 
    int m= accumulate(A,A+size)/size;
 
    cout<<"result="<<m<<endl;
 
    delete[] A;
 
    getchar();
    return 0;
}

int main(int argc, char **argv) {
    int n;
    cout << "Vvedite kol-vo chisel: ";
    cin >> n;
    readSequenceAndPrintAverage(n);
    return 0;
}

#include <iostream.h>
 
double SR(int *begin, int *end) {
    int numberOfElements = end - begin;
    int sum = 0;
    while (begin != end) {
        sum += *begin++;
    }
    return (double)sum / numberOfElements;
}
 
void readSequenceAndPrintAverage(int n) {
    int *vector = new int[n];
    cout << "Please, enter " << n << " elements." << endl;
    for (int i = 0; i < n; ++i) {
        cout << "Vvidite chislo " << i << ": ";
        cin >> vector[i];
    }
    cout << "SREDNEE ARIFMETICHESKOE " << SR(vector, vector + n) << endl;
    delete [] vector;
}
 
int main(int argc, char **argv) {
    int n;
    cout << "Vvedite kol-vo chisel: ";
    cin >> n;
    readSequenceAndPrintAverage(n);
    return 0;
}