A string s0 is given, only consisting of 0 and 1. The j-th character of the string si is si,j , when the index starts from 0. We defifine si as follows: The length of si is less than the length of si1 by 1. And for each letter si,j in the string si , si,j = max. For example, if s0 = 1010, then s1 = 111, s2 = 11, etc. f represents the number of 1 in the string s. Please print the result ofΣi=0kfSigma_{i=0}^{k}fΣi=0kf.
A string s0 is given, only consisting of 0 and 1. The j-th character of the string si is si,j , when the index starts from 0. We defifine si (i ≥ 1) as follows: The length of si is less than the length of si−1 by 1. And for each letter si,j in the string si , si,j = max(si−1,j , si−1,j+1). For example, if s0 = 1010, then s1 = 111, s2 = 11, etc. f(s) represents the number of 1 in the string s. Please print the result of Σi=0kf(si)Sigma_{i=0}^{k}f(s_{i})Σi=0kf(si).
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