Arrays and Iteration

Find Maximum

Scan the array once, keeping the largest value seen so far. The replay highlights when a candidate replaces the running maximum.

Algorithm

Basic Implementation

basic.f90 
program array_find_max
    implicit none
    integer :: arr(8) = [3, 1, 4, 1, 5, 9, 2, 6]
    integer :: best, i
    best = arr(1)
    do i = 2, 8
        if (arr(i) > best) then
            best = arr(i)
        end if
    end do
    print '(I0)', best
end program array_find_max

Complexity

  • Time: O(n)
  • Space: O(1)

Implementation notes

  • Keep the explicit control flow. Library shortcuts would hide the state changes this lesson is meant to replay.
  • The final output is intentionally small and deterministic for cross-language comparison.
execution replay The checked-in replay follows the language-neutral state table for `array-find-max`.
cross-language comparison This Fortran DSA version keeps the same data and final output as every other DSA book in this wave.