Lab April 17

Problem 1 Write the following functions:

1. Function sumEven that accepts two parameters - integer array and its size and returns the sum of the even elements of the array. If there are no even elements, the function returns -1.

2. Function countEventhat accepts two parameters - integer array and its size and returns the number of the even elements of the array.

3. Function averageEven that accepts two parameters - integer array and its size and returns the average of the even elements. If there are no even elements the function returns -1. This function MUST use functions sumEven and countEven to perform the task

Write a program that randomly generates the size of the array (integer between 5 and 20) and an array of integers between 0 and 10. Use function make_array we wrote in class. Print randomly generated an array using function print_array we wrote in class. The program will use function averageEven to find the average of the even elements

Problem 2

1. Function count_even_divisor that accepts one integer parameter num and returns the number of even divisors of parameter num

2. Function array_even_divisor that accepts two parameters - integer array and its size and for each element of the array prints the number of the even divisors. Use function count_even_divisor.

Write a program that randomly generates the size of the array (integer between 5 and 20) and an array of integers between 0 and 100. Use function make_array we wrote in class. Print randomly generated an array using function print_array we wrote in class. The program will use function array_even_divisor to print even the number of even divisors of each element of the array. Make sure that you specify the case with no even divisors.

Problem 3 Selection Sort:
Write a program that sorts the array of integers using Selection Sort.
Definition: Selection Sort works as follows: first find the smallest element in the array and exchange it with the element in the first position, then find the second smallest element and exchange it with the element in the second position, and continue in this way until the entire array is sorted. You would need to write the following functions:

int min(int A[], int left, int right) - finds and returns the position of the minimal element in sub-array of A between positions left and right
void SelectionSort(int A [], int size) - sorts the array A using Selection Sort algorithm
void ReadArray (int A [] , int size) - reads an array A
void WriteArray (int A [] , int size) - prints an array A

Problem 4:
Write the following functions:

Function sum_divisor that accepts one integer parameter num and returns the sum of the PROPER divisors of the parameter num.
Function isabundant that accepts one integer parameter and returns 1 if the number is abundant and 0 otherwise. Definition: an abundant number or excessive number is a number for which the sum of PROPER divisors is larger than the number itself. Use functin sum_divisors that you wrote, to find the sum of proper divisors. Examples: 12 is abundant, since the sum of the proper divisors is 1+2+3+4+6=16 > 12 20 is abundant, since the sum of the proper divisors is 1+2+4+5+10=22 > 20 6 is NOT abundant, since the sum of proper divisors is 1+2+3 = 6 and it is NOT larger than 6 10 is not abundant, since the sum of proper divisors is 1 + 2 + 5 = 8 < 10
int array_abundant that has two parameters: array of integers and size of the array. The function returns the number of abundant numbers among array elements.

Problem 5
Write main to test your program. You can also write functions make_array and print_array.

In this program you can assume that ALL INPUTS ARE POSITIVE NUMBERS. Write the following functions:

int count_digit(int num) - finds and returns the number of digits of parameter num
void make_array(int array[], int size) - makes an array of size integers. Make it USER INPUT for testing purposes.
void print_array(int array[], int size) - prints arrayof size elements
double ave(int A[], int size) - that has 2 parameters, array of integers and size of the array. The functioin returns the average of numbers that have 2, 3, or 4 digits, or 0 if there are no ints that have 2, 3, or 4 digits. Use function count_digit to find the number of digits in each element.