if two numbers overlap a 5x number

Needed this for battery-shallow-discharge project.

//bug: (10, 6) returns true incorrectly.
bool isOverlap5x(current, last):
    if current < last:
        return isOverlap5x(last, current)
    else if current == last:
        return current %5 == 0
    return current/5 > last/5

bool is5xoverlap(current, last):
    if current < last:
        for i = current+1, i <= last, i++:
            if i%5 == 0:
                return true
    else if current > last:
        for i = a-1, i >= last, i--:
            if i%5 == 0:
                return true
    if current == last:
        if last %5 == 0:
            return true
    return false