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C. A-B PalindromeYou are given a string s consisting of the characters ‘0’, ‘1’, and ‘?’. You need to replace all the characters with ‘?’ in the string s by ‘0’ or ‘1’ so that the string becomes a palindrome and has exactly a characters ‘0’ and exactly b

There are n piranhas with sizes a1,a2,…,an in the aquarium. Piranhas are numbered from left to right in order they live in the aquarium.Scientists of the Berland State University want to find if there is dominant piranha in the aquarium. The piranha is ca