Ceaser Cipher


Loops are also a great way to work with String values.

Let's say we wanted to count the number of times the letter "a" appears in a string. We need to look at each character in the string and check if it is an "a".

We can do this using the code below:

Let's say we wanted to modify the string and replace all the a's with *'s. How we can do this?

We'll first need to declare a new empty string to hold the new string. newString = "". We can then iterate over each character in our string and:

  • If the character is an a, then we add * to our new string
  • else we add the current character to our new String.

Now it's your turn. In the program below, replace all the "a"s with the letter "z", and create a variable named numberOfZs and set that equal to the number of "z"s that apprear in the new String.

Replace a with z
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