#include <iostream>

using namespace std;
const int n = 5;
float a[n + 1];
int fmax(float a[], int nach, int kon);

int main() {
    int i, k; for(i = 1; i <= n; i++) {
        cout << "n введи a[" << i << "] ";
        cin >> a[i];
    } for(i = 1; i <= n; i++) {
        cout << " a[" << i << "]=" << a[i];
    }
    cout << "n";
    cout << fmax(a[5], 0, 4); return(0);
}
int fmax(float a[], int nach, int kon)
{
    int k, kmax;
    float max;
    kmax = nach;
    max = a[nach];
    for(k = nach; k <= kon; k++)
    {
        if(a[k] > max)
        {
            max = a[k]; kmax = k;
        }
    }
    return kmax;
}

#include <iostream>
#include <vector>
#include <limits>

int max(const std::vector<int>::const_iterator& begin, std::vector<int>::const_iterator& end, int curentMax)
{
    if(begin == end)
        return curentMax;
    if(*begin > curentMax)
        return max(begin + 1, end, *begin);
    return max(begin + 1, end, curentMax);
}

int main()
{
    std::vector<int> array{1, 55, 17, 77, 88, 13, 45, 72, 11};
    std::cout << max(array.сbegin(), array.сend(), std::numeric_limits<int>::min()) << "n";
}

template<class ForwardIt>
ForwardIt max_element(ForwardIt first, ForwardIt last, ForwardIt largest)
{
  if (first == last)  // no more elements to compare
    return largest;

  if (*largest < *first) // compare with the first element
    largest = first;

  ++first;
  return max_element(first, last, largest); // compare the rest
}

template<class ForwardIt>
ForwardIt max_element(ForwardIt first, ForwardIt last)
{
  return max_element(first, last, first);
}

#include <iostream>

int main()
{
  float a[] = {1, -2, 3, 0.5};
  std::cout << *max_element(a, a + sizeof(a) / sizeof(*a)) << 'n';
}

$ g++ max_recursive.cc && ./a.out
3

int* max_element(int* first, int* last, int* largest)
{
  for ( ; first != last; ++first)
    if (*largest < *first)
      largest = first;

  return largest;
}

// Максимальный элемент в массиве array с индексами [start,stop)
int maxel(int * array, int start, int stop)
{
    if (start == stop-1) return array[start];
    int mid = (start + stop)/2;
    int m1 = maxel(array,start,mid), m2 = maxel(array,mid,stop);
    return (m1 > m2) ? m1 : m2;
}


int main(int argc, const char * argv[])
{
    int x[] = { 1,2,15,2,41,18,-4,2 };
    cout << maxel(x,0,sizeof(x)/sizeof(x[0]));
}