By the early 1990s, there were more than 150.c mputer viruses in the
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world. Some of these viruses were more “intelhgent' than others: they
had special software which made ①(アi穫 イfor ウvery difficult_エto
ew different
オpeople カカfight) the viru One prOgrarnner Wrote 8
yjruses around this time』証還 9
he (or she) probaD5MW
sm ーー Tn 0996和ie明
