#include <bits/stdc++.h>
using namespace std;
int solve(vector<int>queueToEat,vector<int>dining) {
	sort(queueToEat.rbegin(),queueToEat.rend());
	sort(dining.rbegin(),dining.rend());
	int ans=0;
	int n=queueToEat.size();
	int m=dining.size();
	int j=0;
	for(int i=0;i<m&&j<n;i++){
		while(queueToEat[j]>dining[i]&&j<n){
			j++;
		}
		if(j>=n)break;
		ans++;
		j++;
	}
	return ans;
}
vector<int> split(string s) {
	s += " ";
	vector<int> res;
	int v = 0, f = 0;
	for (char c : s) {
		if (isdigit(c)) {
			f = 1;
			v = v * 10 + c - '0';
		} else {
			if (f) res.push_back(v);
			v = f = 0;
		}
	}
	return res;
}
int main() {
	string s1, s2;
	getline(cin, s1, ']');
	getline(cin, s2);
	vector<int>a = split(s1);
	vector<int>b = split(s2);
	cout << solve(a, b) << '\n';
}