Using arrays in C++

Simple example with arrays in C++. This reminds pretty much of C style code, but is written in C++. The task is to create two static arrays, that can have at maximum 100 elements. Fill them with random elements in the range [10, 40]. We should also provide methods to compute the sum of the two arrays, printing an array and computing the number of odd elements of an array.
Note: For the random numbers, we used this method.

#include <iostream> // header for printing
#include <ctime>    // header for random numbers
#include <cstdlib>  // header for rand
using namespace std;

// return a random number inside the range [min, max]
int randomRange(int min, int max);

// fill randomly the array in range [10, 40]
void fill(int* array, const int N);

// compute the sum of two arrays
int array_sum(const int* a, const int* b, const int N);

// print an array
void print(const int* array, const int N);

// compute the number of elements of the array, that are odd numbers
int number_of_odds(const int* array, const int N);

int main() {
	int a[100], b[100], N;

	// read size of arrays
	do {
		cout << "Input size for arrays (between 0 and 100). Arrays will have the same size\n";
		cin >> N;
	}while(N < 0 || N > 100);
	
	// call this only once, to seed the random generator
	srand( (unsigned int)time ( NULL ) );

	// fill the arrays
	fill(a, N);
	fill(b, N);

	// compute sum of arrays and then print it
	cout << "Sum = " << array_sum(a, b , N) << endl;

	// print both arrays
	print(a, N);
	print(b, N);

	// compute the number of odd elements per array
	cout << "Number of odd elements in array a: " << number_of_odds(a, N) << endl;
	cout << "Number of odd elements in array b: " << number_of_odds(b, N) << endl;

	return 0;
}

// return a random number inside the range [min, max]
int randomRange(int min, int max) {
    return ( rand() % ( max - min + 1 ) ) + min;
}

// fill randomly the array in range [10, 40]
void fill(int* array, const int N) {
	for(int i = 0 ; i < N ; ++i)
		array[i] = randomRange(10,40);
}

// compute the sum of two arrays
int array_sum(const int* a, const int* b, const int N) {
	int sum = 0;
	for(int i = 0 ; i < N ; ++i)
		sum += a[i] + b[i];
	return sum;
}

// print an array
void print(const int* array, const int N) {
	for(int i = 0 ; i < N ; ++i)
		cout << array[i] << " ";
	cout << endl;
}

// compute the number of elements of the array, that are odd numbers
int number_of_odds(const int* array, const int N) {
	int number_of_odds = 0;	
	for(int i = 0 ; i < N ; ++i)
		if(array[i] % 2 != 0)	// if array[i] is NOT even (then it's odd)
			number_of_odds++;
	return number_of_odds;
}

Relevant question in Stackoverflow.

Have questions about this code? Comments? Did you find a bug? Let me know!😀
Page created by G. (George) Samaras (DIT)

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