A lower bound on branching programs reading some bits twice
نویسندگان
چکیده
منابع مشابه
Neither Reading Few Bits Twice nor Reading
We rst consider so-called (1; +s)-branching programs in which along every consistent path at most s variables are tested more than once. We prove that any such program computing a characteristic function of a linear code C has size at least 2 (minfd 1 ; d 2 =sg) , where d 1 and d 2 are the minimal distances of C and its dual C ?. We apply this criterion to explicit linear codes and obtain a sup...
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We first consider so-called (1,+s)-branching programs in which along every consistent path at most s variables are tested more than once. We prove that any such program computing a characteristic function of a linear code C has size at least 2Ω(min{d1, d2/s}), where d1 and d2 are the minimal distances of C and its dual C ⊥. We apply this criterion to explicit linear codes and obtain a super-pol...
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By k n branching programs b p s we mean those b p s which during each of their computations are allowed to test at most k n input bits repeatedly For a Boolean function J computable within polynomial time a trade o has been proven between the number of repeatedly tested bits and the size of each b p P which computes J If at most bpn log c n c repeated tests are allowed then the size of P is at ...
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ژورنال
عنوان ژورنال: Theoretical Computer Science
سال: 1997
ISSN: 0304-3975
DOI: 10.1016/s0304-3975(96)00183-1