test=list(input().split())
dic={"a":1,"b":1,"c":1,"d":2,"e":2,"f":2,"g":3,"h":3,"i":3,"j":4,"k":4,"l":4,"m":5,"n":5,"o":5,"p":6,"q":6,"r":6,"s":6,"t":7,"u":7,"v":7,"w":8,"x":8,"y":9,"z":9}
A=test[2:]
if test[0].isdigit():

    for _ in range(int(test[0])):
        m=int(test[1])
        tempdic=dict()
        for i in A:
            key=''
            for j in i:
                key+=str(dic[j])
            tempdic[int(key)]=tempdic.get(int(key),0)+1
        ans=max(tempdic,key=lambda x:tempdic[x])
        print(ans)

else:
    A=test[2:]
    tempdic=dict()
    for i in A:
        key=''
        for j in i:
            key+=str(dic[j])
        tempdic[int(key)]=tempdic.get(int(key),0)+1
    ans=max(tempdic,key=lambda x:tempdic[x])
    print(ans)