enter the string: 
51 56 2d 10 39 64 ffffffe5 47 ffffffb5 ffffffb5 ffffffcd 1d 21 ffffff82 fffffff5 6a fffffff9 45 5d 24 9 ffffffd5 53 ffffffd3 4d ffffff81 ffffffab ffffffd9 ffffffb1 ffffffb3 59 2d 15 ffffffdf 7d ffffffc0 ffffffa9 ffffffe0 79 10 11 11 11 11 11 3e 35 ffffffc4 1d ffffffaa 11 11 ffffff91 42 45 ffffffcc ffffff95 52 11 11 11 ffffffbc ffffffcb 46