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Guri likes strings. He is also interested in algorithms. A few days ago he discovered for himself a very nice problem: You are given an AB-string S. You need to count the number of substrings of S, which have an equal number of 'A'-s and 'B'-s. Do you know how to solve it? Good. Guri will make the problem a little bit more difficult for you. You are given an ABC-string S. You need to count the number of substrings of S, which have an equal number of 'A'-s, 'B'-s and 'C'-s. A string is called AB-string if it doesn't contain any symbols except 'A' or 'B'. A string is called ABC-string if it doesn't contain any symbols except 'A', 'B' or 'C'. Input: The first line of the input contains an ABC-string S. Output: Your output should contain the only integer, denoting the number of substrings of S, which have an equal number of 'A'-s, 'B'-s and 'C'-s. The answer can go above a 32-bit integer. Please, use 64-bit integers for storing and processing data. Constraints: 1 ≤ |S| ≤ 1 000 000; where |S| denotes the length of the given ABC-string. Time Limit: 1 sec Example 1: Input ABACABA Output 2 Sample I/O Explanation: In the example you should count S[2..4] = "BAC" and S[4..6] = "CAB". |
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Answer» what is these what the HECK is this |
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