# K Gram

def generate_kgrams(text, k):
    m=0
    n=k
    l=[]
    while(n<=len(text)):
        l1=" "
        for i in range(m,n):
            if text[i] == " ":
                l1 += '$'
            else:
                l1 += text[i]
        l.append(l1)
        m+=1
        n+=1
    return l
    
text = input("Enter the sentence : ")
text = " "+text+" "
k = int(input("Enter the value of k : "))
kgram = generate_kgrams(text,k)

print(kgram)