n, k = map(int, input().split())
S = list(map(int, input()))
T = [1 ^ (S[i] & S[i + 1]) for i in range(n - 1)]
x = (len(T) - k) // 2
T = T[x:len(T) - x]
if len(T) != k:
    T = [1 ^ (T[i] & T[i + 1]) for i in range(k)]
print(*T, sep="")