在 mips 中打印直角三角形

Question

这是我写的代码来尝试解决这个问题。 我的代码要结束； 根本没有循环，而且似乎只为输入的任何数字打印两颗星。

li $t1,1 #start row at 1
li $t2,1 #start col at 1
li $t3,0 #temp=0

outer:
bgt $t1,$t0,done  #row < user input
addi $t1,$t1,1 #row++



inner:
bgt $t2,$t1,done  #col<row
addi $t2,$t2,1 #col++

#print star
la $a0,Star
li $v0,4
syscall

addi $t3,$t3,1 #adds 1 to temp after every print

beq $t2,$t3,outer #if col = temp counter  jump to outer

j inner #restart loop

#code to endl;
la $a0,endl
li $v0,4
syscall

j outer #restart loop

以下是预期输出的示例：

Please enter the edge length of the base of right triangle: 5 
* 
** 
*** 
**** 
***** 

Answer 1

您不需要在单个循环中使用多个分支语句。 您的代码只打印两颗星的原因是您没有将内部循环的计数器重置为 1。因此它循环两次，然后退出循环。

这是我的代码，它完全符合您的要求：

.data
    prompt: .asciiz "Please enter the edge length of the base of right 
                      triangle: "
    newLine: .asciiz "\n"
    star: .asciiz "*"

.text
    main:
        li $v0, 4       # print the prompt
        la $a0, prompt
        syscall

        li $v0,5            #take user input
            syscall
    
        move $s0, $v0     # move the input to $s0

        li $t0, 0       # load 0 at t0

    outerLoop:
        beq $t0, $s0, end   #(for i=0;i<=baseLength;i++)
                    #if t0=s0 branch to end
        
        addi $t0, $t0, 1    # increment i

        li $t1, 1       #load 1 at t1

        jal changeLine      #jump to changeLine

    innerLoop:
        bgt $t1, $t0, outerLoop  #(for j=0;j<=i;j++)
                     # if t1=t0 branch to outerLoop

        li $v0, 4       # print star
        la $a0, star
        syscall 
    
        addi $t1, $t1, 1    # increment j

        j innerLoop     # jump to innerLoop

    changeLine: 
        li $v0, 4       # new line
        la $a0, newLine
        syscall 

        jr $ra          # jump to after the call instruction

    end:
        li $v0, 10      # end of program
        syscall

Answer 2

.data prompt: .asciiz "请输入直角三角形底边的长度：" ExitMsg: .asciiz "退出程序。" star: .asciiz "*" newLine: .byte '\\n' .text ## 你的主线程序会询问用户直角三角形底边的长度。 输入：
li $v0, 4 la $a0, 提示系统调用

li $v0,5            #take in input
    syscall

    #This will take the edge length of the base of the right triangle as argument $a0.
    move $a0, $v0           #move the input to a0

    # If user enter 0 or a negative number, the program exits.
    bgtz $a0, printTriangle     #branch if greater than zero

    li $v0, 4
la $a0, ExitMsg
syscall

    li $v0,10           #end program
    syscall

    # Otherwise, the program will pass the edge length value in $a0 to the printTriangle procedure, which will print the triangle as described.
    printTriangle:          #Write a procedure called printTriangle. 
    li $t0, 1           #keep track vervicle
    li $t1, 1           #keep track Horizontal
    move $t3, $a0           #INPUT INT as t3

    # It will then print the triangle with stars. 
    loop:
    li $v0, 4
    la $a0, star
    syscall

    beq $t0, $t1, exitLoop          #if counter 0 = counter 1, exitLoop to new line
    #print an *
    addi $t0, $t0, 1            #otherwise incriment t0 location in array
    j loop                  #looping up to beginning

exitLoop:   
    li $v0, 4               #print newline
    la $a0, newLine
    syscall

    beq $t1, $t3, input             #if t1 = INPUT INT as t3, The mainline code will then loop back to ask the user for a new edge length.

    #else
    li $t0, 1               #set t0 back to 0
    addi $t1, $t1, 1            # incriment t1 location in array    
    j loop