即使運行for循環,列表中的變量'operations'也在更改,儘管它們沒有明確指出其值要更改的行。這裏是我的代碼:雖然沒有明確的變化,但列表變量的值仍在變化
validOperations = ['(', ')', '^', '*', '/', '+', '-']
operations = ['+', '*', '/']
newOp = operations
for y in range(len(newOp) - 1):
for z in range(len(newOp) - 1):
if(validOperations.index(newOp[z]) > validOperations.index(newOp[z+1])):
oldVal = newOp[z]
newOp[z] = newOp[z+1]
newOp[z+1] = newOp[z]
print(newOp)
print(operations)
我能做些什麼,以使其到業務的價值保持不變?
'newOp = operations'不會複製。請參閱http://nedbatchelder.com/text/names.html – user2357112