Finding the last statement in string of atmost similar pattern

amma has asked for the wisdom of the Perl Monks concerning the following question:

I have following data as a string filehandle and I want to find the last statement of repeated pattern!!

abc(1) = xyz(0);
abc(2) = xyz(1);
abc(3) = xyz(2);
...............:
abc(10) = xyz(9);
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I would like to find the abc(10) = xyz(9);