#include <iostream>
#include <cstdio>
#include <cstdlib>
#define LENGTH 32
#define MAXN 100000
using namespace std;
typedef struct node{
        node *next[2];
        bool flag;
};

node Head;
node arr[LENGTH * MAXN];
int nodeCount;

node *GetNewNode(){
        if (nodeCount >= LENGTH * MAXN) {
                printf("ERROR : node count full!");
                exit(1);
        }
        arr[nodeCount].next[0] = NULL;
        arr[nodeCount].next[1] = NULL;
        arr[nodeCount].flag    = false;
        return &(arr[nodeCount++]);
}

void Init(){
        nodeCount = 0;
        Head.next[0] = NULL;
        Head.next[1] = NULL;
        Head.flag    = false;
}

void insertNode(unsigned int num){
        node *p = &Head;
        int temp;
        for (int i = LENGTH - 1; i>=0; i--){
                if (((1<<i)&num) != 0){
                        temp = 1;
                } else {
                        temp = 0;
                }
                
                if (p->next[temp] == NULL){
                        p->next[temp] = GetNewNode();
                }
                
                p = p->next[temp];
        }
        p->flag = true;
}

unsigned int searchNode(unsigned int s){
        unsigned int k;
        node *p = &Head;
        int temp;
        k = 0;
        for (int i = LENGTH - 1; i>=0 ;i--){
                if (((1<<i)&s) != 0){
                        temp = 0;
                } else {
                        temp = 1;
                }
                
                if (p->next[temp] == NULL){
                        k = (k << 1) + (temp ^ 1);
                        p = p->next[temp ^ 1];
                } else {
                        k = (k << 1) + temp;
                        p = p->next[temp];
                }
        }
        return k;
}

int main(){
        int n , m ;
        unsigned int k , s;
        Init();
        int case_count = 0;
        scanf("%d", &case_count);
        int case_index = 0;
        while ((case_count--) && scanf("%d%d" , &n , &m) != EOF){
                case_index++;
                printf("Case #%d:\n", case_index);
                Init();
                for (int i = 0; i < n; i++){
                        scanf("%u",&k);
                        insertNode(k);
                }
                for (int i = 0; i < m; i++){
                        scanf("%u" , &s);
                        k = searchNode(s);
                        printf("%u\n" , k);
                }
        }
        return 0;
}