1. The role of the final function

nums =  list(map(int,  input().strip().split()))

Explain the specific meaning first:
Since INPUT () obtains the string type, turns into integer through the int function;
Since the map returns a iterator, the list is added to a list;

input(). strip(). split()：
The function of implementation is divided by space, and multiple data is entered at the same time;

Input input function, and the role of placing (), split () with strip (), split ():
Delete the input head and the space in the tail;
Then the input is divided into multiple according to the space, and returns in the form of a list;

2. The role of a single function

print("\n  1. ----- .strip()  method --------\n")
# Delete the leftmost and right side of the string, the specified string,
# As long as the specified characters appear on both sides, they will be deleted. By default, the specification string is a space;
str = " NNN I am a  student  NNN   "
print("*___*", str)
print("*___*", str.strip())   # By default, delete the space at the head and tail;
print("*___*", str.strip(' N'))   # Delete the characters specified in the head and tail. Note that if there is a space on the head at this time, the space must be added here;
print("*___*", str.strip(" student")) # Can only be removed, the prescribed characters in the head and tail in the string;


print("\n  2. ----- .split()  method --------\n")
# Return to a list, consisting of STR after SP division,; SP default situation is a space;
#  str.split( sp, num);
# When the separators are not specified, the default is the space, and it includes the change of the line, the watchmaking \ t, but it cannot be the empty "";
# Num is to generate (NUM + 1) string according to the number of split segments of SP, which is divided according to SP;

str = "\nLine1-abc \nLine2-def \nLine3-ghi \nline4-hahaha line5-nnnn"
print (str.split())      # By default, as long as the default separators are included, the segmentation is divided;
print(str.split(" ",2 ))
print (str.split(' ', 4))


print("\n  3. ----- .input()  method --------\n")
# input () function to accept a standard input data and return the String type;
# Since the string type is obtained through INPUT, it turns into integer through int;
# nums1 = list(map(int, input().strip().split()))
print("please input a int list: ")
nums1 = list(map(int,  input().strip().split()))
print("output nums1: \n", nums1)



print("\n  4. ----- .map()  method --------\n")
# MAP (fun1, Iteraable), according to the FUN1 function, map the Iterable sequence;
# Python3 returns the iterator, you need to add the List to convert the iterator into list;
# list(map(fun2, iterable) )

def fun1(x):
    return x*x
print(list(map(fun1, nums1)))