a=list(map(int,input().split()))
n=len(a)
left=0
right=n-1
key=int(input())
while left<=right:
    k=(left+right)//2
    if key==a[k]: break
    elif key>a[k]:
        left=k+1
        print(a[k])
    else: right=k-1 print(a[k])
if key==a[k]:
    print(k+1)
else: print('未找到')