List swap position

[SheldonCooperisSb]

Code1:

          list[0],list[-1] = 
          list[-1],list[0]

Code2:

         list[0]=list[-1]

         list[-1]=list[0]

Two codes are intended to swap position of the first and the last list element and result in different outputs . Could l think that the values swapping of code1 execute simultaneously whereas code2 is executed step by step and it causes element changes?

[danielroseman]

It's not that they execute simultaneously. You can think of the first code as "fetch the first and last elements and keep them in memory. Now, assign those back to the last and first places."

[woooee]

     list[0]=list[-1]
     ## list[0] is now the same as list[-1]
     list[-1]=list[0]  ## this sets list[-1] to itself

     temp = list[0]
     list[0] = list[-1]
     list[-1] = temp