You are given a string sss of length nnn consisting of lowercase English letters. A ybbybbybb substring ttt is defined as a substring of sss which meets the following conditions: The length of ttt is not less than 333. Formally, ∣t∣≥3|t|ge 3∣t∣≥3. The first character of ttt is yyy, and the other characters are bbb. You should count the number of ybbybbybb substrings. A substring of a string sss is a sequence sl,sl+1,…,sr for some integers (l,r)(l,r) such that ,,, in which nnn is the length of the string sss.
You are given a string sss of length nnn consisting of lowercase English letters. A ybbybbybb substring ttt is defined as a substring of sss which meets the following conditions: The length of ttt is not less than 333. Formally, ∣t∣≥3|t|ge 3∣t∣≥3. The first character of ttt is yyy, and the other characters are bbb. You should count the number of ybbybbybb substrings. A substring of a string sss is a sequence sl,sl+1,…,srs_l, s_{l+1}, dots, s_rsl,sl+1,…,sr for some integers (l,r)(l, r)(l,r) such that (1≤l≤r≤n),(1le lle rle n),(1≤l≤r≤n), in which nnn is the length of the string sss.
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