String like s = "1001" and K , convert into string of all zeros

we are given a binary string like s = “010011110” and K , we can invert the values in the window of K length and we can use as many inversion as we want And we have to tell whether we can change the string into all zeros. s = “1001” with K = 3 step could be s-> “0111” → “0000” .
Can anyone explain the approach.