在while语句中使用Python等效的&&（逻辑与）时，出现“ SyntaxError：无效语法”

Question

考虑以下代码：

def subir_norte(altitudes,inicio):
     a3=altitudes[inicio[0]][inicio[1]]
     a4=altitudes[j][inicio[1]]
     p=[a,inicio[1]]
     for j in range(inicio[0]-1,-1,-1):
         while a4 < a3:
             a=j+1
         elif ((a4 >= a3) and j=0):
             a=0
         else subir_norte(altitudes,inicio)
      return p

当我尝试运行该程序时，它在第七行显示“ SyntaxError：语法无效”。 我该如何解决？

Answer 1

On this line

elif ((a4 >= a3) and j=0):

The j=0 should have a double equals as in python equality is written using two equals so it should be

elif ((a4 >= a3) and j==0):

on another note the brackets are not neccesary (but don't change anything) so you could write it as

elif a4 >= a3 and j == 0:

Another issue is that this elif is part of a while loop so it should either be part of and if statement or an if statement itself.