Objective

Write an ARM program that takes a string as input and outputs the number of vowels in the string.

Here is pseudocode for the solution:

Input: string

Output: print out of integer number of vowels in string

Pseudocode:

Print greeting and ask for string

use printf, format string is argument to printf, place in $x0$

Set a saved register $($x$19-$x$27)$ to zero to be used as a counter

Scanf to read input

format string is first argument, place in $x0$

address in memory where string will be put is second argument

Load the input char from memory into a register $--$ Idrb

Check if the char is a null or newline chararacter, if it is$,$ go to step $8$

Otherwise check if the char is a vowel $($i$.$e$.$ compare the char with the ascii values of $A,E,$I,$O,U,a,e,i,o,u$

If it is a value, increment the counter register

Go to step $4$

Use printf to print the counter's value

$x0$ contains format string, $x1$ contains a value to replace the format specifier with

Run exit sequence

Compiling and Running Your Code

Compiling:

gcc $-$o pa$1$ pa$1.$s $-$g

Running:

$./$pa$1$