Leftmost occurrence

#find if the element is in the list
#list ISN'T sorted

n = int(input())
a = list(map(int, input().split()))
x = int(input())

a.sort()

#we consider elements in positions [l, r) -- a[l], a[l + 1], ..., a[r - 1].

l = -1
r = n
while l < r - 1: #there is more than one element
    m = (l + r) // 2 #look at the value in the middle
    if a[m] < x:
        l = m
    else:
        r = m
if r < n and a[r] == x: #if r ==n than there are no elements equal to x
    print('The leftmost occurrence is', r)
else:
    print('There is no such element')