Function to count odd numbers

# Counts the number of odd integers in x (the argument vector) 
#First define the function countoddnum

countoddnum <- function(x) { 
#k (a counter) is used to count the number of odd numbers in x.
  k <- 0 
#In each iteration, n takes the value of the corresponding element x
#In test case one below , the loop iterates 7 times because the vector x has 7 elements.
  for (n in x) {
    if (n %% 2 == 1) k <- k+1
  }
  return(k)
  } 
#Then call the function on a couple of test cases

#Test case one
#It can be seen that x contains 4 odd numbers for test case one
countoddnum(c(1,3,5,23,22,44,66))

## [1] 4

#Test case two
countoddnum(c(1,2,3,7,9,78,90,115))

## [1] 5

#Try this: alter the function to count even numbers
#Answer: if(n %% 2==0)