.data
prompt:		.asciiz		"\n Please input an integer value for P: "
result1:	.asciiz		"The number is prime."
result2:	.asciiz		"The number is not prime."

			.globl 		main
			.text
main:       
			li			$v0, 4   	         	# Print prompt.
            la			$a0, prompt
            syscall
            li			$v0, 5	            	# Read P.
            syscall
            move		$t0, $v0       			# P in $t0.
			addi		$t1, $zero, 4
isprime:	sub			$sp, $sp, $t1  			# allocate stack
			sw			$ra, 0($sp)
			bgt			$a0, 1 if1				# if (i > 1) branch to if1
			li			$v0, 1
			move		$a0, $t0
			syscall
			li			$v0, 4
			la			$a0, result1
			syscall
			j			exit
if1:		rem			$t0, $a0, $a0			# rem = (P % i)
			bne			$t0, $zero, if2			# if (rem != 0), branch to if2
			li			$v0, 0
			move		$a0, $t0
			syscall
			li			$v0, 4
			la			$a0, result2
			syscall
			j			exit
			addi		$t2, $zero, 1
if2:		sub			$a0, $a0, $t2			# i = i - 1
			jal			isprime
exit:		lw			$ra, 0($sp)				# restore ra
			add			$sp, $sp, 4				# cleanup stack
			jr			$ra						# return $v0