def iter_exprs(num_operands=None):
    if num_operands is None:
        i = 1
        while True:
            yield from iter_exprs(i)
            i += 1
    elif num_operands == 1:
        yield "1"
    else:
        for i in range(1, num_operands):
            for left in iter_exprs(i):
                for right in iter_exprs(num_operands-i):
                    for operator in ["+", "*"]:
                        yield f"({left}{operator}{right})"

for x in iter_exprs():
    print(x)