3 replies to this topic

[BrownianMan]

Hey, new to the forum.

I'm currently taking my first programming course, and in one of the assignments, I was asked to trace the following Fortran77 program fragment by hand and determine the final values for n and m:

integer n, m, k, j

n = 0

m = 0

do k = 1, 3

     do j = k, 1, -1

         n = n + j

     end do

     m = m + k

end do

print*, n

print*, m

I was only able to get this far:

n m k j
0 0 1 1
1 1 2 0
3 3 3 2


How should I approach it from here?

[WingedPanther]

I would slow down. For each row, only update one variable. You may want to also indicate the line that updated the variable. You cannot have two variables updated at once.

[BrownianMan]

What happens when k becomes higher than 3 though? Shouldn't it exit the loop?

[WingedPanther]

n=n+j gets processed 6 times. You've skipped some executions.