#include <vector>
#include <algorithm>
#include <iostream>

using namespace std;


struct v2
{
    int a;
    int b;
};

bool sort1(v2 a, v2 b){
    if(a.a == b.a)
        return a.b < b.b;
    return a.a < b.a;
}
bool sort2(v2 a, v2 b){
    if(a.b == b.b)
        return a.a < b.a;
    return a.b < b.b;
}

int main()
{
    int n, x, y=0;
    cin >> n;
    cin >> x;
    cin >> y;
    vector<v2> cs; // list of competition starts and end times
    for(int i =0;i<n;i++)
    {
        v2 a;
        cin >> a.a;
        cin >> a.b;
        cs.push_back(a);
    }

    vector<int> is; //in wormholes
    vector<int> es; //out wormholes
    for(int i =0;i<x;i++)
    {
        int ax = 0;
        cin >> ax;
        is.push_back(ax);
    }
        for(int i =0;i<y;i++)
    {
        int ax = 0;
        cin >> ax;
        es.push_back(ax);
    }

    //sort in ascending order
    sort(is.begin(), is.end());
    //sort first by end time, then matched ones are sorted by start time in ascending
    sort(cs.begin(), cs.end(), sort2);
    sort(es.begin(), es.end());

    //compare every single to find the best way giving O(n^3) but because the arrays are
    //already sorted we just need to check the first element that fits the condition
    //after this the index is saved so that again in next loop we don't check from the beginning
int out = 1000000;
    int* dp = new int[x]();
    int p1 =0, p2=0;
    for(int i = 0;i<x;i++)
    {
        for(int ab = p1; ab<n;ab++)
        {
            if(cs[ab].a > is[i])
            {
            //          cout << "B" << is[i] << "\n";

                bool tset = false;
                for(int ac = p2;ac<y;ac++)
                {
            //      cout << "C" << es[ac] << "\n";
                    if(cs[ab].b <= es[ac])
                    {

            //cout << "A: " << cs[ab].a << " " << is[i] << " " << es[i] << "\n";
                        int time= es[ac] - is[i] + 1;
                        if(time < out)
                            out = time;
                        tset =true;
                        break;
                    }

                    p2 = ac;
                }
                if(tset)
                    break;
            }

            p1 = ab;
            //p1++;
        }
    }
    cout << out;

}