MIPS: Printing Out a Histogram - mips

Question

I'm writing a MIPS program (assembly language) that takes in 10 integers and prints out a histogram represented by asterisks.
E.g.:
User input of 1, 2, 3, 4
Output:
*
**
***
****
I have most of this code written already in MIPS. The problem I am running into is printing out the correct length of asterisks. As of now it is simply printing out the a histogram all of the same length; the FIRST user inputed integer.
# program functionality:
.data
menu: .asciiz "\n1. New Histogram\n2. Print Histogram\n3. Quit\n"
prompt: .asciiz "\nEnter 10 numbers between 0 and 50 (inclusive):\n"
prompt1: .asciiz "\nEnter a valid number:\n"
asterisk: .asciiz "*"
space: .asciiz "\n"
array: .word 0:10
.text
main:
do:
jal print_menu
li $v0, 5
syscall
beq $v0, 1, new
beq $v0, 2, print
beq $v0, 3, quit
j do # end do
new:
jal new_user
j do
print:
jal print_user
j do
j quit
print_menu:
la $a0, menu
li $v0, 4
syscall
jr $ra
new_user:
la $a0, prompt
li $v0, 4
syscall
enter_loop:
la $t0, array
li $t1, 10
enter_loop_2:
la $a0, prompt1
li $v0, 4
syscall
li $v0, 5
syscall
sw $v0, ($t0)
addi $t1, $t1, -1
beqz $t1, end_loop_2
addi $t0, $t0, 4
j enter_loop_2
end_loop_2:
jr $ra
print_user:
la $t0, array
li $t1, 10
pLoop:
la $a0, space
li $v0, 4
syscall
asterisk_fun:
li $v0, 1
lw $a0, ($t0)
syscall
counter:
la $a0, asterisk
li $v0, 4
syscall
addi $a0, $a0, -1
beqz $a0, asterisk_end
j counter
asterisk_end:
jr $ra
addi $t1, $t1, -1
beqz $t1, endpLoop
addi $t0, $t0, 4
j pLoop
endpLoop:
jr $ra
quit:
li $v0, 10
syscall

Answer 1

The problems is that you are overwriting register $a0 in counter with the address of the asterisk, and you also used $a0 to count the number of items in that bucket.
Easy solution is to use other register (e.g. $a1) to count the number of items:
That would be:
#... your code
asterisk_fun:
li $v0, 1
lw $a1, ($t0) # Load number in $a1
move $a0, $a1 # move to $a0 just to print it
syscall
la $a0, asterisk
counter:
li $v0, 4
syscall
addi $a1, $a1, -1 # we use $a1 to keep the counter
beqz $a1, asterisk_end
j counter
asterisk_end:
# ... more of your code