Python For，While循环:将if- into改为循环

Question

我是一个新的学习者，我的问题是我如何将这些if-else语句转换为for while循环？

我试图用一种愚蠢的方法，我的逻辑如下：

1.输入号码列表

2.使用给定向量中的操作数来进行数学运算。

3.输出结果

谢谢。

int= [1, 6, 8, 4]  # input int
operands=['+', '-', '*'] # input operands

sum = '+'
sub = '-'
multi = '*'
divide = '/'
z = 1
temp =0
if operands[0] == sum:
    temp = int[0]+int[1]
elif operands[0] == sub:
    temp =int[0] -int[1]
elif operands[0] == multi:
    temp =int[0] *int[1]
elif operands[0] == divide:
    temp = int[0]/int[1]

if operands[1] == sum:
    temp += int[2]
elif operands[1] == sub:
    temp -= int[2]
elif operands[1] == multi:
    temp *= int[2]
elif operands[1] == divide:
    temp /= int[2]
if operands[2] == sum:
    temp += int[3]
elif operands[2] == sub:
    temp -= int[3]
elif operands[2] == multi:
    temp *= int[3]
elif operands[2] == divide:
    temp /= int[3]
    
print(temp)

Answer 1

我想，用于循环是你所需要的

ints = [1, 6, 8, 4]  # input int
operands = ['+', '-', '/'] # input operands

plus = '+'
minus = '-'
multi = '*'
divide = '/'
z = 1

temp = ints[0]

for i in range(len(operands)): # We need to get range from 0 to length of operands

    if operands[i] == plus:
        temp = temp + ints[i + 1]
    elif operands[i] == minus:
        temp = temp - ints[i + 1]
    elif operands[i] == multi:
        temp = temp * ints[i + 1]
    elif operands[i] == divide:
        temp = temp / ints[i + 1]

print(temp)

还要记住，将变量命名为int或sum是个坏主意，因为它是内置的python函数。

Answer 2

首先是'+‘、'-’、'*‘这些都被称为运算符..

你可以从这里得到帮助。

lst = [1, 6, 8, 4]  # input int
operators =['+', '-', '*'] # input operators

sum = '+'
sub = '-'
multi = '*'
divide = '/'
z = 1
temp =0
for i in range(len(lst)-1):
    if i < len(lst):
        if operators[i] == sum:
            temp = lst[i] + lst[i + 1]
        elif operators[i] == sub:
            temp = lst[i] - lst[i + 1]
        elif operators[i] == multi:
            temp = lst[i] * lst[i + 1]
        elif operators[i] == divide:
            temp = lst[i] / lst[i + 1]
print(temp)

Answer 3

这可能会有帮助

lst= [1, 6, 8, 4]  # input int
operands=['+', '-', '*'] # input operands
temp=lst[0]

for i in range(len(lst)-1):
  expr = "temp="+str(temp)+operands[i]+str(lst[i+1])
  exec(expr)

print(temp)