#include <cstdio>
#include <iostream>

using namespace std;

int main()
{
    int n,s,r,k[15],i,br,z[100];
    cin >> n >> s >> r;
    for (i=1;i<=n;++i) k[i]=1;
    for (i=1;i<=s;++i) {cin >> br; --k[br];}
    for (i=1;i<=r;++i) {cin >> br; ++k[br];}
    for (i=1;i<=n;++i)
    {
        if (k[i]==0)
            if (k[i-1]>1) {--k[i-1]; ++k[i];}
        else if (k[i+1]>1) {--k[i+1]; ++k[i];}
    }
    br=0;
    for (i=1;i<=n;++i) if (k[i]==0) ++br;
    cout << br;
    return 0;
}