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Given a list of integers, return the starting index of the first pair that occurs. If there are no pairs in the list, return -1. A pair consists of two consecutive integers having the same value. Three or more values in a row do NOT make or contain a pair. Input Format Input is two lines of data. First line is n, the number of elements in the integer list. Second line is the list of numbers. Constraints first line - n - will be between 2 and 1000000 the values will be any valid java integer values. Output Format output a single integer value - the index of the first element of the pair of value. if no pair exists, then output-1 Sample Input o 14 12 2 2 3 3 4 5 5 5 4 4 41 Sample Output o 4 Explanation 0 There is a single pair of numbers 3 and 3 located at indices 4 and 5 in the list. The starting index is 4 so that is displayed. Sample Input 1 5 33333 Sample Output 1 Explanation 1 Five numbers in a row don't qualify as a pair, so we output-1