scheduling

from collections import deque

jobs = [int(n) for n in input().split(', ')]
idx = int(input())

element = 0
if 0 <= idx < len(jobs):
    element = jobs[idx]

clock_cycles = 0
sorted_jobs = deque(sorted(jobs))
while sorted_jobs:
    current_element = sorted_jobs.popleft()
    if current_element <= element:
        clock_cycles += current_element
    else:
        break

print(clock_cycles)