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Input
A list of nonnegative integers.
Output
The largest nonnegative integer h such that at least h of the numbers in the list are greater than or equal to h.
Test Cases
[0,0,0,0] -> 0
[12,312,33,12] -> 4
[1,2,3,4,5,6,7] -> 4
[22,33,1,2,4] -> 3
[1000,2,2,2] -> 2
[23,42,12,92,39,46,23,56,31,1...