dicH = {}
dicW = {}
lstH = []
lstW = []
for i in range(3):
    h, w = map(int, input().split())
    lstH.append(h)
    lstW.append(w)
dicH[lstH[0]] = "A"
dicH[lstH[1]] = "B"
dicH[lstH[2]] = "C"
dicW[lstW[0]] = "A"
dicW[lstW[1]] = "B"
dicW[lstW[2]] = "C"
    
lst = list(set(lstH))
ans = ""
if len(lst) < 3:
    
    if lstH[0] == lstH[1] and lstH[0] > lstH[2]:
        if lstW[0] > lstW[1]:
            ans = "BAC"
        else:
            ans = "ABC"
    elif lstH[0] == lstH[1] and lstH[0] < lstH[2]:
        if lstW[0] > lstW[1]:
            ans = "CBA"
        else:
            ans = "CAB"
            
    elif lstH[0] == lstH[2] and lstH[0] > lstH[1]:
        if lstW[0] > lstW[2]:
            ans = "CAB"
        else:
            ans = "ACB"
    elif lstH[0] == lstH[2] and lstH[0] < lstH[1]:
        if lstW[0] > lstW[2]:
            ans = "BCA"
        else:
            ans = "BAC"
            
    elif lstH[1] == lstH[2] and lstH[1] > lstH[0]:
        if lstW[1] > lstW[2]:
            ans = "CBA"
        else:
            ans = "BCA"
    elif lstH[1] == lstH[2] and lstH[1] < lstH[0]:
        if lstW[1] > lstW[2]:
            ans = "ACB"
        else:
            ans = "ABC"

    else:
        lstW.sort()
        ans = dicW[lstW[0]] + dicW[lstW[1]] + dicW[lstW[2]]
        
    lst_ans = list(ans)
    print(lst_ans[0] + "\n" + lst_ans[1] + "\n" + lst_ans[2])
else:
    lstH.sort()
    print(dicH[lstH[2]] + "\n" + dicH[lstH[1]] + "\n" + dicH[lstH[0]])