import string

WIN = float('inf')
LOSE = float('-inf')

def ag(x,y):
    if x == LOSE or y == LOSE:
        return LOSE
    else:
        return max(x,y)

t = int(input())
for case in range(1,t+1):
    s = f"Case #{case}:"
    r, c = map(int, input().split())
    data = ['#'*(c+2)]
    for _ in range(r):
        data.append('#'+input()+'#')
    data.append('#'*(c+2))
    starts = {}
    finishes = {}
    for i in range(r+2):
        for j in range(c+2):
            if data[i][j] in string.ascii_lowercase:
                starts[i,j] = data[i][j]
            elif data[i][j] in string.ascii_uppercase:
                finishes[i,j] = data[i][j]
    reachable = [[{f:None for f in finishes} for _ in range(c+2)] for _ in range(r+2)]
    def safe_path(r1,c1,goal,old,n):
        if (r1,c1) == goal:
            return WIN
        elif (r1,c1) in old:
            return old[r1,c1]
        elif data[r1][c1] == '*':
            return LOSE
        elif data[r1][c1] == '#':
            return n+1
        elif reachable[r1][c1][goal] != None:
            return reachable[r1][c1][goal]
        new_old = old.copy()
        new_old[r1,c1] = n
        v_result = ag(safe_path(r1-1,c1,goal,new_old,n-1),safe_path(r1+1,c1,goal,new_old,n-1))
        h_result = ag(safe_path(r1,c1-1,goal,new_old,n-1),safe_path(r1,c1+1,goal,new_old,n-1))
        result = max(v_result,h_result)
        if result < n+1:
            result = LOSE
        if result in (WIN, LOSE):
            pass
            #reachable[r1][c1][goal] = result
        return result
    wins = []
    for start in starts:
        for finish in finishes:
            if safe_path(start[0],start[1],finish,{},0) == WIN:
                wins.append(f" {starts[start]}{finishes[finish]}")
    if wins == []:
        wins.append(" NONE")
    s += ''.join(sorted(wins))
    print(s)