Задать значения вещественным элементам массивов A(6),B(3),C(10) и вычислить Y=max(max(A),max(B),max(C)

#include <iostream>
#include <vector>
#include <algorithm>
#include <iterator>
#include <random>
 
double Max(std::vector<double> a) { return *std::max_element(a.begin(), a.end()); }
 
double Max(double a, double b) { return a >= b ? a : b; }
 
double Max(double a, double b, double c) { return Max(a, Max(b, c)); }
 
int main()
{
    std::default_random_engine gen{ std::random_device()() };
    std::uniform_real_distribution<> dist(-10, 10);
    std::vector<double> a(6), b(3), c(10);
    std::generate(a.begin(), a.end(), [&dist, &gen]() {return dist(gen); });
    std::copy(a.begin(), a.end(), std::ostream_iterator<double>(std::cout, " "));
    std::cout << "\n";
    std::generate(b.begin(), b.end(), [&dist, &gen]() {return dist(gen); });
    std::copy(b.begin(), b.end(), std::ostream_iterator<double>(std::cout, " "));
    std::cout << "\n";
    std::generate(c.begin(), c.end(), [&dist, &gen]() {return dist(gen); });
    std::copy(c.begin(), c.end(), std::ostream_iterator<double>(std::cout, " "));
    std::cout << "\n\nMax = " << Max(Max(a), Max(b), Max(c))<<"\n";
    system("pause");
    return 0;
}

#include <iostream>
using namespace std;
 
int main()
{   
    double A[6], B[3], C[10], maxA=0, maxB=0, maxC=0;   
    cout <<"Enter matrix A:\n";
    for (size_t i = 0; i < 6; i++)    
    cin >> A[i];
 
    for (size_t i = 0; i < 6; i++)
    {
    cout << A[i] << "  ";
    if (i==0 || A[i]>=maxA) maxA=A[i];
    }    
    cout <<"\nmaxA="<<maxA;
    
    cout <<"\nEnter matrix B:\n";
    for (size_t i = 0; i < 3; i++)    
    cin >> B[i];
 
    for (size_t i = 0; i < 3; i++)
    {
    cout << B[i] << "  ";
    if (i==0 || B[i]>=maxB) maxB=B[i];
    }    
    cout <<"\nmaxB="<<maxB;
     
    cout <<"\nEnter matrix C:\n";
    for (size_t i = 0; i < 10; i++)    
    cin >> C[i];
 
    for (size_t i = 0; i < 10; i++)
    {
    cout << C[i] << "  ";
    if (i==0 || C[i]>=maxC) maxC=C[i];
    }    
    cout <<"\nmaxC="<<maxC<<endl;
    if (maxA>=maxB&&maxA>=maxC) cout <<"Y="<<maxA<<endl;
    else if (maxB>maxA&&maxB>maxC) cout <<"Y="<<maxB<<endl;
    else cout <<"Y="<<maxC<<endl;
system("pause");
return 0;
}

#include <algorithm>
#include <vector>
#include <iostream>
#include <iterator>
#include <random>
 
int main()
{
    std::vector<double> a(6), b(3), c(10);
 
    auto gen_prt = [](auto &v)
    {
        static std::default_random_engine gen{ std::random_device()() };
        static std::uniform_real_distribution<> dist(-10.5, 10.5);
        std::generate(std::begin(v), std::end(v), [] { return dist(gen); });
        std::copy(begin(v), end(v), std::ostream_iterator<double>(std::cout, "   "));
        std::cout << '\n';
    };
 
    gen_prt(a); gen_prt(b); gen_prt(c);
 
    auto max_el = [](const auto & v1) {
        return *std::max_element(cbegin(v1), cend(v1));
    };
 
    std::cout << "\n Max_element = " << std::max({ max_el(a), max_el(b), max_el(c) });
 
    system("pause");
}