问题
我的解答思路和尝试过的方法
def twonums_sum(n,lst):
for x in lst:
for y in lst:
if x + y == n:
result = print(lst.index(x),"+",lst.index(y))
else:
result = print('-1')
return result
def main():
number = input("Please input a number as the sum.")
list = input("Please input a list.")
twonums_sum(number,list)
if name == 'main':
main()
运行结果及报错内容
返回的数值全是“-1”