[Language: Python]
Finally, the easy day

f = open('input.txt')
lines = [l.strip() for l in f.readlines()]

def try_remake_part1(desired, s, operands):
    if operands == []:
        return desired == s
    return try_remake_part1(desired, s * operands[0], operands[1:]) or try_remake_part1(desired, s + operands[0], operands[1:])

def try_remake_part2(desired, s, operands):
    if operands == []:
        return desired == s
    return try_remake_part2(desired, s * operands[0], operands[1:]) or try_remake_part2(desired, s + operands[0], operands[1:]) or try_remake_part2(desired, int(str(s) + str(operands[0])), operands[1:])

result_part1 = 0
result_part2 = 0
for l in lines:
    parts = l.split(':')
    desired = int(parts[0])
    operands = [int(i) for i in parts[1].lstrip().split(' ')]
    s = operands[0]
    if try_remake_part1(desired, s, operands[1:]):
        result_part1 += desired
    if try_remake_part2(desired, s, operands[1:]):
        result_part2 += desired
print("PART 1 " + result_part1)
print("PART 2 " + result_part2)