def main():
    import sys
    input = sys.stdin.read
    data = input().split()
    N = int(data[0])
    K = int(data[1])
    S = data[2]
    t = N - K
    result = []
    for i in range(K):
        # Compute window of size t+1 starting at i
        window = S[i:i+t+1]
        current = [c == '1' for c in window]
        for _ in range(t):
            next_current = []
            for j in range(len(current)-1):
                a = current[j]
                b = current[j+1]
                next_current.append(not (a and b))
            current = next_current
        result.append('1' if current[0] else '0')
    print(''.join(result))
    
if __name__ == "__main__":
    main()