Question

Python problem:

How do you include the number that you are trying to process if it's the sentinel?  This is my solution won't include -999 in the process, but I am not sure how do this...

# write a program that prints out the average of # the negative numbers in the list that appear before a -999 is detected.

def main(): MyList = [ 23, -45, 6, -23, -9, 77, 54, -54, 21, -2, 8, -3, -23, 45, 93, -43, -999, -2, 3, 78, 90 ]

count_neg = 0 # count of negative numbers

total_neg = 0 # sum or total of negative numbers

for num in MyList:

if num < 0: # check for negative numbers count_neg += 1 total_neg = total_neg + num

elif (num == 999): # stops when it finds 999 break

# output

print("Average negative number is : ", total_neg*1.0/count_neg)

main() print("The end of processing")

Answer 1

def main():
    MyList = [23, -45, 6, -23, -9, 77, 54, -54, 21, -2, 8, -3, -23, 45, 93, -43, -999, -2, 3, 78, 90]
    count_neg = 0  # count of negative numbers
    total_neg = 0  # sum or total of negative numbers
    for num in MyList:
        # Just check for sentinel first and then process data
        if num == -999:  # stops when it finds 999
            break
        if num < 0:  # check for negative numbers
            count_neg += 1
            total_neg = total_neg + num
    # output
    print("Average negative number is : ", total_neg * 1.0 / count_neg)


main()
print("The end of processing")