# Author: Heidi Ellis
# Date: 09/13/05

# Given an array of integers, this program
# prompts the user for an integer and prints
# all numbers greater than or equal to the input 
# number in correct order and the numbers lower
# than the input number in reverse order. 
# Note: Try entering 2147483645!
	.data

# Define array size in memory.
size:      .word 4

# Define array in memory.
arrayA:    .word 12
           .word 15
           .word 23
           .word 45
      

# Data for prompts and user feedback.
newln:     .asciiz "\n"	# Newline string
prompt:    .asciiz "Enter an integer: "
larger:    .asciiz "Numbers larger than input: \n"
smaller:   .asciiz "Numbers smaller than input: \n"
goodbye:   .asciiz "Good-bye! \n"

	.text

main:	la      $t1, arrayA    # Put start address of array into $t1
	                       # $t1 will hold array index for loop
	lw      $s0, size      # Put size in $s0

	li      $s1, 1         # Set $s1 as loop counter

	li      $v0, 4         # Prompt user to enter integer
	la      $a0, prompt
      syscall

	li      $v0, 5          # Read in integer 
      syscall
      move    $s2, $v0        # Store in $s2

	li      $v0, 4          # Print "larger" heading
	la      $a0, larger   
	syscall

# Beginning of loop to print if number
# is greater than the input integer.

 aloop:	bgt     $s1, $s0, next   # $s0 is loop bound, $s1 is counter 
        	 
            lw      $s3, 0($t1)     # Retrieve array element
       
	      blt     $s3, $s2, inc   # Branch to loop end if not greater than

	      li      $v0, 1          # Else print array element
	      move	  $a0, $s3        
	      syscall  
	      li      $v0, 4          # Print newline character
	      la      $a0, newln   
	      syscall

inc:	      addi    $t1, 4          # Increment address counter by 4!
	      addi    $s1, 1          # Increment loop counter

	      j aloop                 # Jump to check if at end of loop

# Loop to print numbers less than input number in reverse order

next:  
            li      $v0, 4          # Print "smaller" heading
	      la      $a0, smaller   
	      syscall

# $t1 holds last address in array

loop2:	blt     $s0, 0, theend   # $s0 size, decremented to zero 
        	 
            lw      $s3, 0($t1)     # Retrieve array element
    
	      blt     $s2, $s3, inc2  # Branch to loop end if not greater than
                                    # I.e., don't print. 
	      li	  $v0, 1          # Else print array element
	      move	  $a0, $s3        
	      syscall  
	      li      $v0, 4          # Print newline character
	      la      $a0, newln   
	      syscall

# On first time through the loop, $t1 contains 
# end address of array. Therefore we'll decrement our
# way back up through the array. 

inc2:	     addi    $t1, -4          # Decrement address counter by 4!
	     addi    $s0, -1          # Decrement loop counter

	     j       loop2            # Jump to check end of second loop


theend:    li      $v0, 4           # Print good bye!
	     la      $a0, goodbye   
	     syscall 
           li      $v0, 10          # Appropriate way to end assembly code
	     syscall