strlen("")=0
strlen("a")=1
strlen("ab")=2
strlen("abc")=3
strlen("abcd")=4
strlen("abcde")=5
strlen("abcdef")=6
strlen("abcdefg")=7
strlen("abcdefgh")=8
strlen("abcdefghi")=9
strlen("abcdefghij")=10
strlen("abcdefghijk")=11
strlen("abcdefghijkl")=12
strlen("abcdefghijklm")=13
strlen("abcdefghijklmn")=14
strlen("abcdefghijklmno")=15
strlen("abcdefghijklmnop")=16
strlen("abcdefghijklmnopq")=17
strlen("abcdefghijklmnopqr")=18
strlen("abcdefghijklmnopqrs")=19
strlen("abcdefghijklmnopqrst")=20
strlen("abcdefghijklmnopqrstu")=21
strlen("abcdefghijklmnopqrstuv")=22
strlen("abcdefghijklmnopqrstuvw")=23
strlen("abcdefghijklmnopqrstuwvx")=24
strlen("abcdefghijklmnopqrstuwvxy")=25
strlen("abcdefghijklmnopqrstuwvxyz")=26
strlen("xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx")=255
strlen("xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx")=256