A program counts the number of words in a string read from the user,and then exits. __ pattern is most suitable for implementing this specification

The simplest pattern to implement the given specification is the linear pattern, also known as the straight-line pattern. The program reads the input string, counts the number of words, and then exits. There are no branches, loops, or other control structures involved. Here is an example implementation in Python using the linear pattern:

sentence = input("Enter a sentence: ")
words = len(sentence.split())
print("The sentence has", words, "words.")

In this implementation, the input sentence is split into words using the split() method and then the number of words is counted using the len() function. Finally, the number of words is printed to the console and the program exits.

相关问题

Write a Python program that counts the number of vowels in a given string using a for loop.

当然可以。下面是一个简单的Python程序，它会使用for循环来计算给定字符串中元音字母的数量：

def count_vowels(s):
    vowels = "aeiouAEIOU"  # 定义包含所有元音字母的字符串
    vowel_count = 0  # 初始化元音计数器

    for char in s:  # 遍历输入字符串中的每个字符
        if char in vowels:  # 如果字符是元音
            vowel_count += 1  # 增加计数

    return vowel_count  # 返回最终的元音数量

# 测试函数
input_string = "Hello, World!"
vowel_count = count_vowels(input_string)
print(f"The number of vowels in '{input_string}' is {vowel_count}.")

这个程序首先定义了一个包含所有元音的字符串，然后通过遍历输入字符串并检查每个字符是否属于元音，累加计数器。最后，它打印出指定字符串中的元音总数。

Write a program that takes a string input from the user and counts the number of unique characters in the string. Note:The program should only count each unique character once, even if it appears multiple times i n the input string. The program should als

o ignore spaces and special characters.

Sure, here's a Python program that does what you asked:

def count_unique_chars(string):
    unique_chars = set()
    for char in string:
        if char.isalnum():
            unique_chars.add(char.lower())
    return len(unique_chars)

user_input = input("Enter a string: ")
print("Number of unique characters:", count_unique_chars(user_input))

Explanation:

- The `count_unique_chars` function takes a string as input and returns the number of unique characters in it.
- We create an empty set called `unique_chars` to keep track of unique characters as we iterate through the string.
- For each character in the string, we check if it is alphanumeric (i.e., a letter or a number), and convert it to lowercase using the `lower()` method. If it is, we add it to the `unique_chars` set.
- Finally, we return the length of the `unique_chars` set, which gives us the number of unique characters in the string.
- In the main program, we prompt the user to enter a string, and then call the `count_unique_chars` function on it. The result is printed to the console.

I hope this helps! Let me know if you have any further questions.