with open('puzzle.txt', 'r') as f:
    lines = f.read().splitlines()

column_a = []
column_b = []

for line in lines:
    new_column_a, new_column_b = line.split('  ')
    column_a.append(new_column_a.strip())
    column_b.append(new_column_b.strip())

similarity = 0

for i in range(len(column_a)):
    for x in range(len(column_b)):
        column_a_instances = 0
        if column_a[i] == column_b[x]:
            column_a_instances += 1

        similarity += column_a_instances * int(column_a[i])

print(similarity)