C Programming Concepts

What is the syntax for declaring a variable in C?

• variable_name = data_type;

• data_type variable_name;

• variable_name : data_type;

• variable_name data_type;

What is the difference between 'int' and 'float' data types in C?

• int stores characters while float stores numbers

• int can store negative numbers while float cannot

• int is used for text data while float is used for numerical data

• The main difference is that 'int' stores whole numbers, while 'float' stores numbers with decimal points.

Explain the 'if-else' statement in C with an example.

• Example: int num = 10; if(num > 5) { printf('The number is greater than 5'); } else { printf('The number is less than or equal to 5'); }

• Example: int x = 5; if(x == 5) { printf('The number is equal to 5'); } else { printf('The number is not equal to 5'); }

• The 'if-else' statement is used for looping in C.

• Example: int num = 10; if(num < 5) { printf('The number is less than 5'); } else { printf('The number is greater than or equal to 5'); }

What is the purpose of 'printf' function in C?

• The purpose of 'printf' function in C is to create a new variable

• The purpose of 'printf' function in C is to read input from the standard input

• The purpose of 'printf' function in C is to print formatted output to the standard output.

• The purpose of 'printf' function in C is to perform mathematical calculations

How do you declare and initialize an array in C?

• data_type array_name = {initialization_values};

• array_name = new data_type[array_size];

• data_type array_name[array_size] = {initialization_values};

• array_name = malloc(array_size * sizeof(data_type));

Explain the concept of 'pointers' in C.

• Pointers in C are used to store the value of another variable.

• Pointers in C are variables that store the memory address of another variable. They are used to access and manipulate the memory directly, allowing for more efficient memory management and data manipulation.

• Pointers in C are only used for accessing memory, not for manipulation.

• Pointers in C are not compatible with other programming languages.

What is the use of 'malloc' function in C?

• The 'malloc' function is used to sort arrays in C.

• The 'malloc' function is used to allocate memory in C.

• The 'malloc' function is used to print output in C.

• The 'malloc' function is used to free memory in C.

What are the different types of loops available in C?

• for loop, while loop, and do-while loop

• if loop

• switch loop

• repeat loop

Explain the concept of 'function' in C with an example.

• A function in C is a variable that holds a block of code that can be executed whenever it is called.

• Example: int multiply(int x, int y) { return x * y; } In this example, 'multiply' is a function that takes two integer parameters 'x' and 'y' and returns their product.

• Example: int add(int a, int b) { return a + b; } In this example, 'add' is a function that takes two integer parameters 'a' and 'b' and returns their sum.

• Example: void printMessage() { printf('Hello, World!'); } In this example, 'printMessage' is a function that prints the message 'Hello, World!' when called.

What is the difference between 'call by value' and 'call by reference' in C?

• In call by value, the actual parameter is passed as a pointer, while in call by reference, the actual parameter is passed as a value.

• In call by value, the function can modify the actual parameter, while in call by reference, the function cannot modify the actual parameter.

• In call by value, the actual parameter is passed by reference, while in call by reference, the actual parameter is passed by value.

• In call by value, a copy of the actual parameter is passed to the function, while in call by reference, the address of the actual parameter is passed to the function.