import sys

input=sys.stdin.readline
m=int(input())
cnt=0
s=list(map(int,input().split()))
n=int(input())
for i in range(1,m-1):
    if s[i]==0 and s[i-1]==0 and s[i+1]==0:
        s[i]=1
        cnt+=1
if n>cnt:
    print("false")
else:
    print("true")