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Solution Review: for Loops

Solution Review: for Loops

In this review, we provide a detailed analysis of the solution to this problem.

We'll cover the following...

Solution #1: Using for Loop

R
testVariable <- c(3, 5, 15)
for (element in testVariable) {
  if(element %% 3 == 0 && element %% 5 == 0)
  {
    cat(element, "foo bar ")
  } else 
  {
    if(element %% 3 == 0)
    {
      cat(element, "foo ")
    }
    if(element %% 5 == 0)
    {
      cat(element, "bar ")
    }
  }
}

Explanation

We have a vector testVariable that contains all the numbers.

We initiate a for loop for all the elements in the vector (line number 2) and check whether that element is a multiple of 33, 55 or both.

Solution #2: Using while Loop

R
testVariable <- c(3, 5, 15)
index <- 1 # variable to iterate over the whole vector
n <- length(testVariable) # length of the vector
while (index <= n) {
  if(testVariable[index] %% 3 == 0 && testVariable[index]  %% 5 == 0)
  {
    cat(testVariable[index], "foo bar ")
  } else 
  {
    if(testVariable[index]  %% 3 == 0)
    {
      cat(testVariable[index], "foo ")
    }
    if(testVariable[index]  %% 5 == 0)
    {
      cat(testVariable[index], "bar ")
    }
  }
  index = index + 1 # increment the index
}

Explanation

Here, we are using a while loop to solve this problem.

Remember we could fetch an element in a vector using square brackets [].

We have fetched all elements of the vector using their indexes, for example, testVariable[1], testVariable[2]…testVariable[n]. Here, n is the last element (placed at length(testVariable)). We iterate over all these indexes starting from 11 to nn using the while loop.

There is another method to make loops using repeat.