Question

Prompt the user and read in a string. Make your string large enough to hold 100 characters.

2. Count the number of words in the string. A word is one or more non-blank characters separated by one or more blanks. My suggestion is to use a flag (a boolean variable) to indicate whether or not you are in a word. Then you know you have found a word when the flag indicates that you are in a word and the next character is a blank. Think about how you will know when you have found the end of a word, and what you should do with your flag at that point.

3. Create a new string which is a copy of the original string, except that the new string is converted to uppercase. All non-letter characters should be unchanged. Convert the letters using difference between the ASCII codes for capital letters and the ASCII codes for small letters. Do not create nested if processing.

4. Print the original string, the new string, and the word count. Make sure you print messages to label your output.

When we call syscall to read in a string, we give a length n in $a1. syscall reads in at most n-1 characters and it adds a null byte (which has the value Oxo) to the end of the string. If the string is less than n-1 characters, then syscall adds a newline (which has the value Oxa) after the null byte. This means that the last word can end with either a blank, the null byte, or a newline. However, since the newline is always followed by the null byte, you can ignore the newline. But you will need to look for the null byte since there may not be a blank after the last

Written in MIPS

Answer 1

Screenshot

#Data declaration part .data prompt: .asciiz "Enter a string: " wordsCount: .asciiz "Words' count = " upperCase: .asciiz "nString after uppercasing = " string: .byte 100 #Program starts her .text #Prompt for string addi $v0,40,4 la Sal, prompt syscall #Read string li $v0,8 la $al, string addi $al,$0,100 syscall #Copy of the string add $50, 90, $al #Call function to count words jal WordCount #Store word count in to temporarly arlrl t an :37 Column: 21 Show Line Numbers ars Messages Run I/O Enter a string: This is my program. Words' count = 4 String after uppercasing = THIS IS MY PROGRAM. Clear |-- program is finished running --

Program

#Data declaration part
.data
    prompt: .asciiz "Enter a string: "
    wordsCount: .asciiz "Words' count = "
    upperCase: .asciiz "\nString after uppercasing = "
    string: .byte 100
  
#Program starts her
.text
    #Prompt for string
    addi $v0,$0,4
    la $a0,prompt
    syscall
    #Read string
    li $v0,8
    la $a0,string
    addi $a1,$0,100
    syscall
    #Copy of the string
    add $s0,$0,$a0
    #Call function to count words
    jal WordCount
    #Store word count in t0 temporarly
    add $t0,$v0,$0
    #Display wor count message
    addi $v0,$0,4
    la $a0,wordsCount
    syscall
    #Display count
    addi $v0,$0,1
    add $a0,$0,$t0
    syscall
    #For uppercase function argument pass
    add $a0,$0,$s0
    #Call function to change uppercase
    jal Uppercase
    #Display message
    addi $v0,$0,4
    la $a0,upperCase
    syscall
    #Display sttring
    add $a0,$s0,$0
    addi $v0,$0,4
    syscall
    #end of the program
    addi $v0,$0,10
    syscall
#Implement a function to count number of words
WordCount:
    #Word count storung variable
    addi $v0,$0,0
    #Variable act as flag
    addi $t1,$0,0
#Loop until reach end of the string
Loop:
    #Get each charecters
    lb $t0,0($a0)
    #Check end of the line
    beq $t0,10,ret
    #Check space
    beq $t0,32,space
    #After space increment
    beq $t1,1,increment
#Loop repetition
Up:
    addi $a0,$a0,1
    j Loop
#Increment word count and reset flag
increment:
    addi $v0,$v0,1
    addi $t1,$0,0
    j Up
#Set flag if space founs
space:
    addi $t1,$0,1
    j Up
#Return to mai
ret:
addi $v0,$v0,1
jr $ra
#Implementation of string uppercase function
Uppercase:
    #Get each charcter
    lb $t0,0($a0)
    #Check end of the string
    beq $t0,10,return
    #Small letter check
    bge $t0,97,next
#Increment address to get next charcter and loop repetition
up:
    addi $a0,$a0,1
    j Uppercase
#Check is small letter
next:
    bgt $t0,122,up
    #Then change into capital
    addi $t0,$t0,-32
    #Restore
    sb $t0,0($a0)
    j up
#go to main
return:
    jr $ra

--------------------------

Output

Enter a string: This is my program.
Words' count = 4
String after uppercasing = THIS IS MY PROGRAM.

-- program is finished running --