papers with citations exactly i, find the h-index of Bobo.
The h-index of an author is the largest h where he has at least h papers with citations not less than h. Bobo has published many papers. Given a_0, a_1, a_2, dots, a_{n} a ,a 1 ,a 2 ,…,a n which means Bobo has published a_i a i papers with citations exactly i, find the h-index of Bobo.
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