Suppose two sequences end at the same position, but start at different good "one" positions, with the first sequence longer (starting before) the second. Let i be the difference between the number of ones and the number of zeros in the first sequence, and let j be the difference between the number of ones and the number of zeros in the second sequence. Can i and j be equal? Consider the part of the first sequence before the second begins. How many ones and zeros could it have?

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