Flow of Control in Programming

Study Notes

Definition: The order in which statements, instructions, or function calls are executed or evaluated.
Basic types:
- Sequential: Instructions are executed one after another.
- Selection (Conditional): Execute code based on a specific condition, using if statements, else statements, and switch statements.
- Iteration (Looping): Repeat code as long as a certain condition remains true, using for loops, while loops, and do-while loops.

Purpose: To execute code only if a specific condition is true.
if statement: Executes code if the condition is true.
else statement: Provides an alternative code block to execute if the if condition is false.
if-else if-else: Handles multiple conditions, executing the code block corresponding to the first true condition.
switch statement: Tests a variable against a list of values, executing corresponding code when a match is found.
break statement: Exits the switch block after a case has been executed, preventing execution of subsequent cases.

Purpose: To repeatedly execute a block of code as long as a specific condition is true.
for loop: Iterates over a sequence of values, controlled by initialization, condition, and update components.
while loop: Executes code while the condition remains true, checking the condition before each iteration.
do-while loop: Similar to while loop, but checks the condition after the loop body executes, ensuring at least one iteration.
continue statement: Skips the current iteration and proceeds to the next iteration.
break statement: Exits the loop immediately, skipping any remaining iterations.
Nested loops: Loops within other loops, where the inner loop executes entirely for each iteration of the outer loop.
- Complexity Consideration: Nested loops can lead to high time complexity (e.g., O(n^2) for two nested loops) as the execution time multiplies.
Entry-controlled loops: Check the condition at the beginning of the loop (e.g., for and while).
Exit-controlled loops: Check the condition at the end of the loop (e.g., do-while).

Definition: A function calling itself to solve a problem by breaking it into smaller, identical subproblems.
Use Cases: Algorithms like tree traversal and factorial calculation.
Potential Concerns: Can lead to stack overflow if the recursion doesn't have a defined base case.

Purpose: To visually represent the flow of control in a program, showing paths based on decisions, loops, and sequences of code.

Infinite loops: Occur when the loop condition never becomes false due to errors in the loop logic.
Ternary operator: A concise form of an if-else statement that takes the format condition ? expression1 : expression2.
Exception handling: Alters the usual flow of control by transferring execution to exception-handling blocks (e.g., try-catch) when errors or exceptions occur.