if-else:

The if-else statement in C is used to make decisions based on conditions. It checks whether a condition is true or false and executes different blocks of code accordingly. If the condition inside the if is true, the corresponding block runs; otherwise, the else block is executed.

We can also use else if to check multiple conditions in sequence. This is useful when you need to compare values using relational or logical operators. Only one block is executed among all the available conditions. The syntax requires the condition to be enclosed in parentheses, and code blocks are wrapped in curly braces. You can nest if statements within each other to handle more complex logic.

This control structure is versatile and allows you to make decisions based on variable values or expressions. It is particularly useful when the number of possible outcomes is limited and conditions are more than just value comparisons. The if-else structure plays a critical role in controlling the flow of a program and improving logical decision-making.

switch:

The switch statement in C is used for multi-way branching based on the value of an expression or variable. It compares the expression against a set of predefined constant values using case labels. When a match is found, the corresponding code block is executed.

Each case should end with a break statement to prevent fall-through, where the execution continues into the next case unintentionally. If no cases match, the optional default block is executed. The switch expression must be of an integer or character type, and it only supports equality checks, not relational operations.

It is best used when a variable can take one out of several fixed values. The structure is simpler and more readable than writing multiple if-else statements, especially when checking the same variable against many possible values. switch improves code clarity and is efficient for handling fixed condition branches. However, it’s important to avoid duplicate case values and to use break consistently to control the flow properly.