The target element variable, the indexes of whose matching elements we will find, is defined below: target_element=2 Example 1: Determine Index of All Matching Elements in List Using for Loop & enumerate() Func
We can get the index of the first element in our list using the index() function.first_index = my_list.index('a') print(first_index) # 0As you can see, my_list.index('a') returns the index of the first element ‘a’ in my_list, which is 0....
可以使用索引来访问列表中的元素,例如list.get(index)可以获取指定索引位置的元素。 可以使用索引来修改列表中的元素,例如list.set(index, element)可以将指定索引位置的元素替换为新的元素。 可以使用索引来删除列表中的元素,例如list.remove(index)可以删除指定索引位置的元素。
my_tuple[2][0]=0# 修改my_tuple的元素列表的内容print(my_list)print(my_tuple) 输出结果: 可见my_list也被修改了 这是因为:python的赋值语句不会创建对象的副本,仅仅创建引用。这里的my_list和my_tuple嵌入的列表共同引用同一个内存对象。 改变my_tuple所引用的对象的值时,my_list的值也会被改变,反之亦...
# 使用for循环遍历列表foriinrange(len(my_list)): 1. 2. 步骤3:判断当前元素是否等于目标元素 # 判断当前元素是否等于目标元素ifmy_list[i]==30: 1. 2. 步骤4:如果相等,则打印出当前元素的索引位置 # 如果相等,则打印出当前元素的索引位置print("Index of element 30 is:",i) ...
3.list中利用索引改变或替换元素值; .set(index, element); //将元素 element放到list中索引为 index的位置,替换原有元素 .add(index, element); //将元素 element放到list中索引为 index的位置,原来位置的元素后移一位 代码示例: String a="张三", b="李四", c="王五", d="赵六"; ...
该方法用于检测某个T对象是否存在于List(T)对象中,List(T).Contains(T)方法继承自ICollection(T).Contains(T),并对其进行了实现。首先看.net中该方法对应的代码 // Contains returns true if the specified element is in the List. // It does a linear, O(n) search. Equality is determined by calling...
print("The index of last occurrence of element is : $index") } Output The index of last occurrence of element is : 3 Example 2: List.lastIndexOf() – Element not in the List In this example, we will try to find the output of List.lastIndexOf() function, when the element is not...
Negative Indexing: Python also supports negative indexing, which starts from the end of the list. This means the last element can be accessed with-1, the second to last with-2, and so forth. In thecolorslist,colors[-1]returns'blue', the last element. ...
The index should only be used for the purpose of accessing the element data at that location or to traverse the list. This is why almost all methods on the Indexes are private. When a new element is inserted in the list, its index will be returned from that method, but the user can ...