H-Index

문제

In research, it is tough to determine how good of a researcher you are. One way that people determine how good you are is by looking at your $HH$-Index.

Each paper has a certain number of citations. Your $HH$-Index is the largest number $HH$ such that you have $HH$ papers with at least $HH$ citations. Given the number of citations on each paper you have written, what is your $HH$-Index?

입력

The first line of input contains a single integer $nn$ ($1\le n\le 1000001\; \backslash leq\; n\; \backslash leq\; 100\backslash ,000$), which is the number of papers you have written.

The next $nn$ lines describe the papers. Each of these lines contains a single integer $cc$ ($0\le c\le 10000000000\; \backslash leq\; c\; \backslash leq\; 1\backslash ,000\backslash ,000\backslash ,000$), which is the number of citations that this paper has.

출력

Display your $HH$-Index.