.data
	array: .word 1, 2, 3, 4, 5, 6
	orig: .asciiz "Original array: "
	rev: .asciiz "\nReverse array: "

.text

main:

	jal printOriginalArray
	jal printReverseArray
		
  	ori $v0, $0, 10       				# system call code 10 for exit
  	syscall               				# exit the program
  	
reverse:
    	bge $a0, $a1, done        			# if the start index is greater or equal to the end index, we are done
    
    		lw $t2, array($a0)        		# load the element at start index
    		lw $t3, array($a1)        		# load the element at end index
    		sw $t3, array($a0)        		# store the element from the end at the start index
    		sw $t2, array($a1)     			# store the element from the start at the end index

    		addi $a0, $a0, 1       			# increment the start index
    		subi $a1, $a1, 1       			# decrement the end index

    		b reverse            			# recursively reverse the remaining elements
    	done: 
    		jr $ra                 			# return to the caller
    	
printOriginalArray:
	li $v0, 4
	la $a0, orig
	syscall

	li $s0, 21					# limit of offsets for 6 elements in the array
	li $v0, 1 					# syscall 1 to print an int
	li $t0, 0
	
	origWhile:
		bge $t0, $s0 origDone			# while the offset is less than 21
			lw $a0, array($t0) 		# load the next word in the array
			syscall				# print
			
			addi $t0, $t0, 4 		# increment the offset by 4
			
			b origWhile			# return to start of while loop
	origDone:
		jr $ra 					# return to caller
		
printReverseArray:
	li $v0, 4
	la $a0, rev
	syscall

	li $s0, -1					# lower limit of 6 offsets
	li $v0, 1 					# syscall 1 to print an int
	li $t0, 20
	
	revWhile:
		bge $s0, $t0 revDone			# while the offset is less than 21
			lw $a0, array($t0) 		# load the next word in the array
			syscall				# print
			
			subi $t0, $t0, 4 		# increment the offset by 4
			
			b revWhile			# return to start of while loop
	revDone:
		jr $ra 					# return to caller