Problem:
Search II

You are given a sequence of n integers S and a sequence of different q integers T. Write a program which outputs C, the number of integers in T which are also in the set S.

Input

In the first line n is given. In the second line, n integers are given. In the third line q is given. Then, in the fourth line, q integers are given.

Output

Print C in a line.

Constraints

Elements in S is sorted in ascending order

n ≤ 100000

q ≤ 50000

0 ≤ an element in S ≤ 109

0 ≤ an element in T ≤ 109

Sample Input 1

5
1 2 3 4 5
3
3 4 1

Sample Output 1

3

Sample Input 2

3
1 2 3
1
5

Sample Output 2

0

Sample Input 3

5
1 1 2 2 3
2
1 2

Sample Output 3

2

Notes

Solution in Rust (judge verdict: Accepted)

use std::io::*;
use std::str::FromStr;
#[allow(unused_imports)]
use std::collections::*;
#[allow(unused_imports)]
use std::cmp::{min, max};

struct Scanner<R: Read> {
    reader: R,
    buffer: String,
}

#[allow(dead_code)]
impl<R: Read> Scanner<R> {
    fn new(reader: R) -> Scanner<R> {
        Scanner { reader: reader, buffer: String::new() }
    }

    // fn line(&mut self) -> String {
    //     self.buffer = self.reader.by_ref().bytes().map(|c| c.unwrap() as char)
    //         .skip_while(|&c| c == '\n' || c == '\r')
    //         .take_while(|&c| !(c == '\n' || c == '\r'))
    //         .collect::<String>();
    //     self.buffer.clone()
    // }

    fn read_buffer(&mut self) {
        self.buffer = self.reader.by_ref().bytes().map(|c| c.unwrap() as char)
            .skip_while(|c| c.is_whitespace())
            .take_while(|c| !c.is_whitespace())
            .collect::<String>();
    }

    fn safe_read<T: FromStr>(&mut self) -> Option<T> {
        self.read_buffer();
        if self.buffer.is_empty() {
            None
        } else {
            self.buffer.parse::<T>().ok()
        }
    }

    fn read<T: FromStr>(&mut self) -> T {
        if let Some(s) = self.safe_read() {
            s
        } else {
            // writeln!(std::io::stderr(), "Terminated with EOF").unwrap();
            std::process::exit(0);
        }
    }

    fn vec<T: FromStr>(&mut self, len: usize) -> Vec<T> {
        (0..len).map(|_| self.read()).collect()
    }

    fn mat<T: FromStr>(&mut self, row: usize, col: usize) -> Vec<Vec<T>> {
        (0..row).map(|_| self.vec(col)).collect()
    }
}

trait Joinable {
    fn join(self, sep: &str) -> String;
}

impl<U: ToString, T: Iterator<Item=U>> Joinable for T {
    fn join(self, sep: &str) -> String {
        self.map(|x| x.to_string()).collect::<Vec<_>>().join(sep)
    }
}

fn main() {
    std::thread::Builder::new()
        .stack_size(104_857_600)
        .spawn(solve)
        .unwrap()
        .join()
        .unwrap();
}

fn solve() {
    let cin = stdin();
    let cin = cin.lock();
    let mut sc = Scanner::new(cin);

    loop {
        let n = sc.read();
        let mut a: Vec<u32> = sc.vec(n);
        a.sort();
        a.dedup();
        let m = sc.read();
        let mut b: Vec<u32> = sc.vec(m);
        b.sort();

        let mut cnt = 0;
        let mut it = a.iter().peekable();
        for &x in b.iter() {
            // println!("{:?}", it);
            while let Some(&y) = it.peek() {
                if y < &x {
                    it.next();
                } else {
                    break;
                }
            }
            while let Some(&y) = it.peek() {
                if y == &x {
                    cnt += 1;
                    it.next();
                } else {
                    break;
                }
            }
        }
        println!("{}", cnt);
    }
}