A skeleton code is provided for you to write a program which will calculate the Fibonacci sequence (0, 1, 1, 2, 3, 5, 8, .). The first n number will be shown as the output, where n will be given by the user. As the first two numbers (0 and 1) are predefined in a Fibonacci sequence, n must be >=3. Otherwise, the program will show an error message. The skeleton program uses two leaf procedures: print_number: this procedure prints an integer followed by a space character. add_two: this procedure does the addition of two integers, save the result in $s0, and return the value of $s0 to the caller. The two following restrictions are added so that you have some practice of using stack in the callee procedure. The input n must be stored in $s0 in the main program. The add_two procedure must use $s0 to save the result of the addition before returning its value to the caller.

main: # Print input prompt li $v0,4 # syscall code = 4 for printing a string la $a0, in_prompt # assign the prompt string to a0 for printing syscall # Read the value of n from user and save to t0 li $v0,5 # syscall code = 5 for reading an integer from user to v0 syscall ### Set s0 with the user input & if invalid (<=2) jumpt to exit_error ### ### Set proper argument register and call the procedure print_numnber to show the first two numbers of the sequence (0 & 1)### li $t0, 2 # initialize counter register t0 ### Load the first two numbers (0 & 1) to s1 & s2 ### loop: ### set the argument registers (a0 and a1) to the last two values in the sequence for addition, and then call proedure add_two### move $s1, $s2 # s1 now stores the last value in the sequence move $s2, $v0 # s2 now new value as returned from the addition procedure move $a0, $v0 # update a0 for printing the returned value jal print_number ### Increment the counter and compare it with user input. If equal, jumpt to exit.### j loop # Go to the start of the loop add_two: ### Push the value of s0 in the stack ### add $s0, $a0, $a1 # s0 now holds the result of the addition ### Set the register that will hold the reutrn value with the result of the addition ### ### Pop the value of s0 from the stack ### jr $ra # return to the caller # segement for printing an integer print_number: ### Write the syscall code for printing the integer ### # syscall for printing a space character li $v0,4 la $a0, space syscall jr $ra #return to the caller # exit block for wrong value of the input exit_error: li $v0, 4 # syscall code = 4 for printing the error message la $a0, error_string syscall li $v0,10 # syscall code = 10 for terminate the execution of the program syscall # exit block for the program exit: li $v0,10 # syscall code = 10 for terminate the execution of the program syscall .data in_prompt: .asciiz "how many numbers in the sequence you want to see (must be at least 3): " error_string: .asciiz "The number ust be greater than or equal to 3" space: .asciiz " "