// 本题为考试单行多行输入输出规范示例，无需提交，不计分。
package Example;
import java.util.*;
/*
2
5 5 1
5 3 4 1 2
0 6 7 9 8
5 5 0
5 3 4 1 2
0 6 7 9 8

0
1
 */




public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int T = sc.nextInt();
        while(T-- > 0){
            int n = sc.nextInt(),m = sc.nextInt(),k = sc.nextInt();
            long[] nums1 = new long[n];
            long[] nums2 = new long[m];
            for(int i = 0;i < n;++i) nums1[i] = sc.nextLong();
            for(int i = 0;i < m;++i) nums2[i] = sc.nextLong();
            Arrays.sort(nums1); Arrays.sort(nums2);


            long t = k;
            long t1 = Math.min(check(nums1,nums2,t),check(nums2,nums1,t));
            long t2 = Math.min(check(nums1,nums2,-t),check(nums2,nums1,-t));
            long res = Math.min(t1,t2);
            System.out.println(res);
        }
    }

    static long check(long[] nums1,long[] nums2,long t){
        int n = nums1.length,m = nums2.length;
        int p1 = 0,p2 = 0;
        long res = Long.MAX_VALUE;
        while(p1 < n && p2 < m){
            long val = nums1[p1] - nums2[p2]-t;
            if(val  == 0) return 0;
            else if(val > 0){
                ++p2;
                res = Math.min(res,val);
            } else ++p1;
        }
        return res;
    }


}