Conditions, loops, and local calculations

The idea

Julia if conditions require boolean values; a number is not automatically treated as true or false. Comparisons such as x > 0 create the boolean decisions needed by branches. A for loop can iterate over values directly or over a range. The range 1:4 includes both endpoints, while a stepped range such as 1:2:5 visits one, three, and five. Check the reachable values before counting iterations.

Place reusable loop calculations inside functions so their working variables have a clear local scope. Initialize an accumulator before the loop, update it only when the condition matches, and return it afterward. This structure naturally handles empty input because the loop body runs zero times. break exits the nearest loop, while continue skips to the next iteration without ending the whole loop.

function positive_total(values)
    total = 0
    for value in values
        if value > 0
            total += value
        end
    end
    total
end
println(positive_total([4, -2, 3]))
println(positive_total(Int[]))

7
0

The function includes four and three but skips the negative entry. Empty input leaves the initialized accumulator unchanged, giving a defined result of zero.