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diff --git a/tutorials/module_1/1_07_control_structures.md b/tutorials/module_1/1_07_control_structures.md deleted file mode 100644 index 15e97eb..0000000 --- a/tutorials/module_1/1_07_control_structures.md +++ /dev/null @@ -1,127 +0,0 @@ -# Control Structures -Control structures allow us to control the flow of execution in a Python program. The two main types are **conditional statements (`if` statements)** and **loops (`for` and `while` loops)**. - -## Conditional Statements - -Conditional statements allow a program to execute different blocks of code depending on whether a given condition is `True` or `False`. These conditions are typically comparisons, such as checking if one number is greater than another. - -### The `if` Statement - -The simplest form of a conditional statement is the `if` statement. If the condition evaluates to `True`, the indented block of code runs. Otherwise, the program moves on without executing the statement. - -For example, consider a situation where we need to determine if a person is an adult based on their age. If the age is 18 or greater, we print a message saying they are an adult. - -### The `if-else` Statement - -Sometimes, we need to specify what should happen if the condition is `False`. The `else` clause allows us to handle this case. Instead of just skipping over the block, the program can execute an alternative action. - -For instance, if a person is younger than 18, they are considered a minor. If the condition of being an adult is not met, the program will print a message indicating that the person is a minor. - -### The `if-elif-else` Statement - -When dealing with multiple conditions, the `if-elif-else` structure is useful. The program evaluates conditions in order, executing the first one that is `True`. If none of the conditions are met, the `else` block runs. - -For example, in a grading system, different score ranges correspond to different letter grades. If a student's score is 90 or higher, they receive an "A". If it's between 80 and 89, they get a "B", and so on. If none of the conditions match, they receive an "F". - -### Nested `if` Statements - -Sometimes, we need to check conditions within other conditions. This is known as **nesting**. For example, if we first determine that a person is an adult, we can then check if they are a student. Based on that information, we print different messages. - - -```python -# Getting user input for the student's score -score = int(input("Enter the student's score (0-100): ")) - -if 0 <= score <= 100: - if score >= 90: - grade = "A" - elif score >= 80: - grade = "B" - elif score >= 70: - grade = "C" - elif score >= 60: - grade = "D" - else: - grade = "F" # Score below 60 is a failing grade - - - if grade == "F": - print("The student has failed.") - retake_eligible = input("Is the student eligible for a retest? (yes/no): ").strip().lower() - - if retake_eligible == "yes": - print("The student is eligible for a retest.") - else: - print("The student has failed the course and must retake it next semester.") - - -``` - ---- - -## Loops in Python - -Loops allow a program to execute a block of code multiple times. This is especially useful for tasks such as processing lists of data, performing repetitive calculations, or automating tasks. - -### The `for` Loop - -A `for` loop iterates over a sequence, such as a list, tuple, string, or a range of numbers. Each iteration assigns the next value in the sequence to a loop variable, which can then be used inside the loop. - -For instance, if we have a list of fruits and want to print each fruit's name, a `for` loop can iterate over the list and display each item. - -Another useful feature of `for` loops is the `range()` function, which generates a sequence of numbers. This is commonly used when we need to repeat an action a specific number of times. For example, iterating from 0 to 4 allows us to print a message five times. - -Additionally, the `enumerate()` function can be used to loop through a list while keeping track of the index of each item. This is useful when both the position and the value in a sequence are needed. - -```python -fruits = ["apple", "banana", "cherry"] -for x in fruits: - print(x) -``` - -```python -for x in range(6): - print(x) -else: - print("Finally finished!") -``` -### The `while` Loop - -Unlike `for` loops, which iterate over a sequence, `while` loops continue running as long as a specified condition remains `True`. This is useful when the number of iterations is not known in advance. - -For example, a countdown timer can be implemented using a `while` loop. The loop will continue decreasing the count until it reaches zero. - -It's important to be careful with `while` loops to avoid infinite loops, which occur when the condition never becomes `False`. To prevent this, ensure that the condition will eventually change during the execution of the loop. - -A `while` loop can also be used to wait for a certain event to occur. For example, in interactive programs, a `while True` loop can keep running until the user provides a valid input, at which point we break out of the loop. - -```python -i = 1 -while i < 6: - print(i) - i += 1 -``` - ---- - -## Loop Control Statements - -Python provides special statements to control the behavior of loops. These can be used to break out of a loop, skip certain iterations, or simply include a placeholder for future code. - -### The `break` Statement - -The `break` statement is used to exit a loop before it has iterated through all its elements. When the `break` statement is encountered, the loop stops immediately, and the program continues executing the next statement outside the loop. - -For instance, if we are searching for a specific value in a list, we can use a `break` statement to stop the loop as soon as we find the item, instead of continuing unnecessary iterations. - -### The `continue` Statement - -The `continue` statement is used to skip the current iteration and proceed to the next one. Instead of exiting the loop entirely, it simply moves on to the next cycle. - -For example, if we are iterating over numbers and want to skip processing number 2, we can use `continue`. The loop will ignore that iteration and proceed with the next number. - -### The `pass` Statement - -The `pass` statement is a placeholder that does nothing. It is useful when a block of code is syntactically required but no action needs to be performed yet. - -For example, in a loop where a condition has not yet been implemented, using `pass` ensures that the code remains valid while avoiding errors. |
