Genos needs your help. He was asked to solve the following programming problem by Saitama: The length of some string s is denoted | s | . The Hamming distance between two strings s and t of equal length is defined as , where s i is the i -th character of s and t i is the i -th character of t . For example, the Hamming distance between string " 0011 " and string " 0110 " is |0 - 0| + |0 - 1| + |1 - 1| + |1 - 0| = 0 + 1 + 0 + 1 = 2 . Given two binary strings a and b , find the sum of the Hamming distances between a and all contiguous substrings of b of length | a | . The first line of the input contains binary string a ( 1 ≤ | a | ≤ 200 000 ). The second line of the input contains binary string b ( | a | ≤ | b | ≤ 200 000 ). Both strings are guaranteed to consist of characters ' 0 ' and ' 1 ' only. Print a single integer — the sum of Hamming distances between a and all contiguous substrings of b of length | a | . For the first sample case, there are four contiguous substrings of b of length | a | : " 00 ", " 01 ", " 11 ", and " 11 ". The distance between " 01 " and " 00 " is |0 - 0| + |1 - 0| = 1 . The distance between " 01 " and " 01 " is |0 - 0| + |1 - 1| = 0 . The distance between " 01 " and " 11 " is |0 - 1| + |1 - 1| = 1 . Last distance counts twice, as there are two occurrences of string " 11 ". The sum of these edit distances is 1 + 0 + 1 + 1 = 3 . The second sample case is described in the statement.