shahab03 0 Light Poster

I am trying to do towers of hanoi recursively below is the code. my problem is that i am not getting out of the cycle at the right time so code keeps on running... can someone tell me what I may be doing wrong?

.data
msg0: .asciiz "Enter number of disks:"
msg1: .asciiz "Move disk 1 from TOWER "
msg2: .asciiz "Move disk "
msg3: .asciiz " from TOWER "
msg4: .asciiz " to TOWER "
msg5: .asciiz "\n"

.text
.globl main
main:	


la $a0,msg0	#Print "Enter number of disks:"
li $v0,4
syscall

li $v0,5	 #cin, $v0=input value
syscall

addi $t0,$zero,6	#$t0=6
move $a2,$v0	#$a2=number of disc,initialized by input value
addi $t7,$zero,1	#$t7=from,initialize to 1
addi $a1,$zero,3	#$a1=to,initialize to 3
move $t1,$t0	#$t1=temp,initialize to $t1=6

addi $sp,$sp,-20	 #create a stack with 5 boxes
sw $ra,16($sp)	 #$ra |retun address|
sw $t7,12($sp)	 #$t7 |from |
sw $a1,8($sp)	 #$a1 |to |
sw $a2,4($sp)	 #$a2 |numberof disc|
sw $t1,0($sp)	 #$t1 |temp |<---$sp

jal hanoi # call hanoi

#lw $ra,16($sp)	 # -----------------(*)

lw $ra,16($sp)	 #$ra |retun address|
lw $t7,12($sp)	 #$t7 |from |
lw $a1,8($sp)	 #$a1 |to |
lw $a2,4($sp)	 #$a2 |numberof disc|
lw $t1,0($sp)	 #$t1 |temp |<---$sp

addi $sp,$sp,20
#jr $ra


hanoi:


sub $t1,$t0,$t7
sub $t1,$t1,$a1	 #temp = 6-from-to



addi $sp,$sp,-20	 #create a stack with 5 boxes

sw $ra,16($sp)	 #$ra |retun address|
sw $t7,12($sp)	 #$t7 |from |
sw $a1,8($sp)	 #$a1 |to |
sw $a2,4($sp)	 #$a2 |numberof disc|
sw $t1,0($sp)	 #$t1 |temp |<---$sp

bne $a2,1,recurse # if (n =/= 1) recurse

li $v0,4
la $a0,msg1
syscall
li $v0,1
move $a0,$t7
syscall
li $v0,4
la $a0,msg4
syscall
li $v0,1
move $a0,$a1
syscall
li $v0,4
la $a0,msg5
syscall

endcase: # exit code

addi $sp,$sp,20	 #delete a stack with 5 boxes

lw $ra,16($sp)	 #$ra |retun address|
lw $t7,12($sp)	 #$t7 |from |
lw $a1,8($sp)	 #$a1 |to |
lw $a2,4($sp)	 #$a2 |numberof disc|
lw $t1,0($sp)	 #$t1 |temp |<---$sp

jr $ra # return

recurse:

addi $a2,$a2,-1

move $a1,$t1

jal hanoi # call hanoi

li $v0,4	#--------------------(**)
la $a0,msg2
syscall
li $v0,1
move $a0,$a2
syscall
li $v0,4
la $a0,msg3
syscall
li $v0,1
move $a0,$t7
syscall
li $v0,4
la $a0,msg4
syscall
li $v0,1
move $a0,$a1
syscall
li $v0,4
la $a0,msg5
syscall

lw $ra,16($sp)	 #$ra |retun address|
lw $t7,12($sp)	 #$t7 |from |
lw $a1,8($sp)	 #$a1 |to |
lw $a2,4($sp)	 #$a2 |numberof disc|
lw $t1,0($sp)	 #$t1 |temp |<---$sp
addi $sp,$sp,20	 #delete a stack with 5 boxes

addi $a2,$a2,-1

move $t7,$t1


jal hanoi # call hanoi

j endcase # goto exit code (return)---------------------(***)
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