python中列表的索引方式有两种顺序:正序和倒序
-
正序索引
列表中所有元素从左至右被标号,从0开始,例如
a = [1,2,3,4,5]
a[0] = 1
a[1] = 2
a[0:2] = [1,2]
...
-
倒序索引
从最后一个元素开始标号,从-1开始,例如
b = [1,2,3,4,5]
b[-1] = 5
b[-2] = 4
b[-3:-1] = [3,4]
...
python中列表的索引方式有两种顺序:正序和倒序
列表中所有元素从左至右被标号,从0开始,例如
a = [1,2,3,4,5]
a[0] = 1
a[1] = 2
a[0:2] = [1,2]
...
从最后一个元素开始标号,从-1开始,例如
b = [1,2,3,4,5]
b[-1] = 5
b[-2] = 4
b[-3:-1] = [3,4]
...