- # http://c...content-available-to-author-only...e.com/a/55082/34718 
- # Author: mbomb007 
-   
- I,c=input() 
- I+=(c-len(I)%c)*" " 
- L=[] 
- i=0 
- while I:s=I[:c];L+=[[s,s[::-1]][i%2]];i+=1;I=I[c:] 
- print"\n".join(L) 
				IyBodHRwOi8vYy4uLmNvbnRlbnQtYXZhaWxhYmxlLXRvLWF1dGhvci1vbmx5Li4uZS5jb20vYS81NTA4Mi8zNDcxOAojIEF1dGhvcjogbWJvbWIwMDcKCkksYz1pbnB1dCgpCkkrPShjLWxlbihJKSVjKSoiICIKTD1bXQppPTAKd2hpbGUgSTpzPUlbOmNdO0wrPVtbcyxzWzo6LTFdXVtpJTJdXTtpKz0xO0k9SVtjOl0KcHJpbnQiXG4iLmpvaW4oTCk=