test = int(input())
for t in range(test):
n , k = map(int,input().split())
s = input()
lastone = -1
count = 0
for i in range(n):
if int(s[i])==1:
if lastone>=max(0,i-k+1) and lastone<=i-1:
count+=1
lastone = i
else:
continue
print(count)
dGVzdCA9IGludChpbnB1dCgpKQpmb3IgdCBpbiByYW5nZSh0ZXN0KToKCW4gLCBrID0gbWFwKGludCxpbnB1dCgpLnNwbGl0KCkpCglzID0gaW5wdXQoKQoJbGFzdG9uZSA9IC0xCgljb3VudCA9IDAKCQoJZm9yIGkgaW4gcmFuZ2Uobik6CgkJaWYgaW50KHNbaV0pPT0xOgoJCQlpZiBsYXN0b25lPj1tYXgoMCxpLWsrMSkgYW5kIGxhc3RvbmU8PWktMToKCQkJCWNvdW50Kz0xCgkJCQlsYXN0b25lID0gaQoJCWVsc2U6CgkJCWNvbnRpbnVlCglwcmludChjb3VudCkKCQkJCQoJCQkKCQk=