Реализация через функцию.

#include "My Library.h"
TYPE Max(TYPE a, TYPE b)
{
return (a>b)?a:b;
}
TYPE Min(TYPE a, TYPE b)
{
return (a<b)?a:b;
}

#include <iostream>
#include <conio.h>
#define size 10
using namespace std;
 
int main(void)
{
    int arr[size];
    int numb,i;
    cout << "Enter el of array:" << "\n";
    for(i=0; i<size; i++)
    {
        cout << "Enter arr ->" << "";  
        cin >> arr[i] ;
    }
    cout << "\n" << "Array -> ";
    for(i=0; i<size; i++)
    {
        cout << arr[i] << " " ;
    }
    cout << "\n" << "Enter numb -> ";
    cin >> numb ;
    cout << "Number el -> ";
     for(i=0; i<size; i++)
     {
         if(numb==arr[i])
         {
             cout << i << " " ;
         }
     }
     getch();
     return 0;
}

#include <iostream>
#include <time.h>
#include <conio.h>
using namespace std;
 
int randMinMax(int min, int max)
{
int x = 0;
do
x = rand() < rand()? rand() * -1 : rand();
while(x < min || x > max);
return x;
}
int main()
{
srand(time(0));
int size = randMinMax(15,30), num;
bool coin = true;
int *matrix = new int[size];
for(int i = 0; i < size; i++)
matrix[i] = randMinMax(-20,20);
for(int i = 0; i < size; i++)
cout << matrix[i] << " ";
cout << "\n" << "Input number:";
cin >> num;
for(int i = 0; i < size; i++)
{
if(matrix[i] == num)
{
cout << "Number " << num << " is numbered " << i << "\n";
coin = false;
}
}
if(coin)
cout << "The matrix of these has been found. \n";
delete[] matrix;
getch();
return 0;
}