More notes on strings

siddharth-krishna · siddharth-krishna · commit e1f41f1c3d65 · 2023-05-11T08:38:16.000+02:00
diff --git a/strings.md b/strings.md
@@ -7,9 +7,12 @@ print(x)
 print(x[3])
 print(x[1:3])
 print(x + ' there')
+print(len(x))
+for c in x:
+    print(c)
 ```
 
-But you cannot modify a list, you have to copy it:
+But you cannot modify a string like you modify a list, you have to copy it:
 ```python
 x = "hello"
 x[3] = 'p'
@@ -31,12 +34,63 @@ name = input("What's your name? ")
 print(f"Hello, {name}")
 ```
 
-More information on strings:
+## Problems
+
+- Write a program that prints each letter of a string and its index
+
+- Write a program that computes the length of a string (without using the `len` function, of course)
+
+- Write a program to ask the user for their full name and converts it into an email address. For example:
+    ```
+    Enter your full name: Boaty McBoatface
+    Your email is boaty.mcboatface@takenolab.com
+    ```
+
+- Write a program that counts the number of words in a string. For example:
+    ```
+    Enter a string: The quick brown fox
+    The string has 4 words in it
+    ```
+
+- Write a program that checks if a string is a number. For example:
+    ```
+    Enter a string: 1234
+    The string is a number
+    Enter a string: 1234e
+    The string is not a number
+    Enter a string: f42kl
+    The string is not a number
+    ```
+
+- Write a program that checks if a string is in snake case. For example:
+    ```
+    Enter a string: a_python_variable
+    The string is in snake case
+    Enter a string: aPythonVariable
+    The string is not in snake case
+    Enter a string: aPython_variable
+    The string is not in snake case
+    ```
+
+- Write a program that checks if a string is in camel case. For example:
+    ```
+    Enter a string: a_python_variable
+    The string is not in camel case
+    Enter a string: aPythonVariable
+    The string is in camel case
+    Enter a string: aPython_variable
+    The string is not in camel case
+    ```
+
+- Write a program that converts a string from snake case to camel case, and another program that converts a string from camel case to snake case.
+
+Once you have completed the problems above, look at the Python documentation to see the inbuilt string functions:
 https://docs.python.org/3/library/stdtypes.html#str
+- Can you simplify your answers to the above problems using the inbuilt functions?
 
-Some problems:
+### Some more problems:
 
-https://py.checkio.org/en/mission/acceptable-password-i/
+https://py.checkio.org/en/mission/acceptable-password-i/ (and then do parts II, III, etc)
 
 https://py.checkio.org/en/mission/backward-string/
 
