#include <iostream>
#include <cstdlib>  // подключаем qsort
#include <cmath>

#define N 27

void fill(int* a){
  for (int i=0; i< N; i++){
     a[i] = -48 + rand()%(59+48+1); // от -48 до 59 включительно
  }
}

void printArr(int* a, char name){
  std::cout << "array "<< name << " :" <<std::endl;
  for (int i=0; i< N; i++){
     std::cout << " " << a[i] ;
  }
  std::cout << std::endl;
}

void printInfo(int* a, int indexFirstEven, int indexLastPositive,  char name){
  std::cout << "FirstEven "
            << name << "[" << indexFirstEven <<"] = "
            <<  a[indexFirstEven] <<std::endl;

  std::cout << "LastPositive "
            << name << "[" << indexLastPositive <<"] = "
            <<  a[indexLastPositive] <<std::endl;
}

int getIndexFirstEven(int* a){
  for (int i=0; i< N; i++){
     if (a[i] %2 == 0)  return i;
  }
  return -1;
}

int getIndexLastPositive(int* a){
  int res = -1;
  for (int i=0; i< N; i++){
     if (a[i]>=0)  res = i;
  }
  return res;
}

int compare(const void * x1, const void * x2)
{
  return ( *(int*)x1 - *(int*)x2 );
}

bool isPrime(int x){
    if (x % 2 == 0) return false;
    int sqrt_x = sqrt(x);
    for (int i=3; i <= sqrt_x; i=i+2){
        if (x % i == 0) return false;
    }
    return true;
}

void printPrimeIndexes(int* a, char name){
  std::cout << "indexes prime numbers in array "<< name << ": " ;
  int count = 0;
  for (int i=0; i< N; i++){
     if ( isPrime(a[i]) ) {
        std::cout << " " << i ;
        count++;
     }
  }
  std::cout << std::endl;
  std::cout << "count prime numbers "<< count << std::endl;
}


int main(){
   int* a = new int[N];
   int* b = new int[N];
   fill(a);
   fill(b);

   printArr(a, 'a');
   printArr(b, 'b');

   int indexFirstEvenA = getIndexFirstEven(a);
   int indexFirstEvenB = getIndexFirstEven(b);

   int indexLastPositiveA = getIndexLastPositive(a);
   int indexLastPositiveB = getIndexLastPositive(b);

   printInfo(a, indexFirstEvenA, indexLastPositiveA, 'a');
   printInfo(b, indexFirstEvenB, indexLastPositiveB, 'b');

   int* beg = a+indexFirstEvenA+1;
   int* end = a+indexLastPositiveA;
   qsort(beg, end-beg, sizeof(int), compare);

   beg = b+indexFirstEvenB+1;
   end = b+indexLastPositiveB;
   qsort(beg, end-beg, sizeof(int), compare);

   printArr(a, 'a');
   printArr(b, 'b');

   printPrimeIndexes(a, 'a');
   printPrimeIndexes(b, 'b');

   delete[] a;
   delete[] b;
}