def common_array_elements(a,b,c):
    da = {}
    db = {}
    dc = {}

    for i in range(0, len(a)):
        da[a[i]]=0
    for i in range(0, len(b)):
        db[b[i]]=0
    for i in range(0, len(c)):
        dc[c[i]]=0

    for i in range(0, len(a)):
        da[a[i]]+=1
    for i in range(0, len(b)):
        db[b[i]]+=1
    for i in range(0, len(c)):
        dc[c[i]]+=1

    suma = 0
    for key in da:
        if key in db and key in dc:
            suma += key * min(da[key], db[key], dc[key])
    return suma

a = [ 1, 2, 2, 3 ];
b = [ 5, 3, 2, 2 ];
c = [ 7, 3, 2, 2 ];

print(common_array_elements(a, b, c))