#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <string>
#include <vector>
#include <algorithm>
#include <cmath>

using namespace std;

int n, s, r;
char k[14]; //0 nista, 1 unisten, 2 rezervni
int t;
int sol = 0;

int main(void) {
	memset(k, 0, sizeof(k));

	scanf("%d %d %d", &n, &s, &r);

	for(int i = 0; i < s; ++i) {
		scanf("%d", &t);
		--t;
		k[t] = 1;
	}

	for(int i = 0; i < r; ++i) {
		scanf("%d", &t);
		--t;
		if (k[t] == 1) k[t] = 0; else k[t] = 2;
	}

	for(int i = 0; i < 11; ++i) {
		if (k[i] == 2) {
			if (i > 0 && k[i - 1] == 1) {
				k[i - 1] = 0;
				k[i] = 0;
			} else if (k[i + 1] == 1) {
				k[i + 1] = 0;
				k[i] = 0;
			}
		}
	}

	for(int i = 0; i < 11; ++i)
		if (k[i] == 1) ++sol;

	printf("%d\n", sol);

	//system("pause");
	return 0;
}