//char s[9];main(n,i){for(i=-scanf("%d",&n);++i<n;printf("a%*s\n",n,s))s[i]=97+i;}
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a a a ab a abc a abcd a abcde a abcdef a abcdefg a abcdefgh a abcdefghi a abcdefghij a abcdefghijk a abcdefghijkl a abcdefghijklm a abcdefghijklmn a abcdefghijklmno a abcdefghijklmnop a abcdefghijklmnopq a abcdefghijklmnopqr a abcdefghijklmnopqrs a abcdefghijklmnopqrst a abcdefghijklmnopqrstu a abcdefghijklmnopqrstuv a abcdefghijklmnopqrstuvw a abcdefghijklmnopqrstuvwx a abcdefghijklmnopqrstuvwxy aabcdefghijklmnopqrstuvwxyz