python中的命令行参数

Question

This is my problem: Through command line arguments three strings separated by space are given to you.Each string is a series of numbers separated by a hyphen(-). You like all the numbers in string 1 and dislike all the numbers in string 2.Third string contains the numbers given to you.your initial happiness is 0. When you encounter a number present in string 1,add 1 to your happiness,if it is present in string 2,add -1 to your happiness.Otherwise your happiness does not change.Output your final happiness at the end.

Sample input: 3-1 5-7 1-5-3-8
Sample output: 1

Explanation: Numbers in string 1: 3,1. Numbers in string 2: 5,7. Numbers given to you: 1,5,3,8. 1 unit of happiness is gained for numbers 1 and 3 which are in string 1.Your total happiness is 2 now. You lose 1 unit of happiness for number 5 which is in string 2. Your total happiness is 1 now.8 is not present in either of strings, so happiness does not change.Final happiness is 1.

This is what I understood. My code for this:

from sys import argv
print("Number in string1:",argv[1])
print("Number in string2:",argv[2])
print("Number in string3:",argv[3])
if i in argv[3]== i in argv[1]:
    count=count+1
if i in argv[3]==i in argv[2]:
    count=count-1
print("Happiness=",count)

But this doesn't work.Please do help me out.I am beginner and command line arguments are really confusing.Thanks in advance.

Answer 1

Frist of all, you will want the take the strings given in the command line arguments and turn them into lists:

liked_numbers = argv[1].split("-")
disliked_numbers = argv[2].split("-")
given_numbers = argv[3].split("-")

Using your sample input this will give you lists in the following format:

liked_numbers = ['3', '1']

disliked_numbers = ['5', '7']

given_numbers = ['1', '5', '3', '8']

Then, you should compare each of your given numbers to the other lists. The following code will first take a number from given_numbers and search for it in liked_numbers, then it will search for it in disliked_numbers, it will do this for every number in given_numbers:

happiness = 0
for num in given_numbers:
    if num in liked_numbers:
        happiness += 1
    if num in disliked_numbers:
        happiness -= 1
print(happiness)