Hi Istvan,

#include adds the iostream library so your C++ program can do input and output, like printing to the screen and reading from the keyboard.

It lets you use things like cout and cin, for example:

#include 
using namespace std;

int main() {
    cout << "Hello";
    return 0;
}

If you have more questions, I am here to help 😊

Hi Jacob,

== compares values after JavaScript may convert one type to another (type coercion).
=== compares both the value and the type, with no conversion.

Example:

5 == "5"    // true (string "5" is converted to number)
5 === "5"   // false (number vs string)

Most of the time, === is safer because it avoids surprising conversions.

If you have more questions, I am here to help 😊

Hi 睿宏,

That happens because printf("%f", ...) shows 6 digits after the decimal by default, so 78.32 becomes 78.320000.

If you want only 2 decimal places, set the precision like this:

printf("%.2f", number);

If you have more questions, I am here to help 😊

Hi Tlachi,

Because pen_number is a number, and "Pens for each student: " is a string. In Python, you cannot join a string and a number using + unless you convert the number to a string first.

So this works:

print("Pens for each student: " + str(pen_number))

Another easy option is to use commas, which avoids str():

print("Pens for each student:", pen_number)

If you have more questions, I am here to help 😊

Hi Gulalai,

C++ helps because it lets you work closer to how the computer actually runs programs.

• You learn how data is stored in memory using things like variables and arrays.

• You can use pointers to see and work with memory addresses.

• C++ code gets compiled into machine code, so it is easier to connect your code to what the CPU executes.

So C++ shows you what is happening under the hood more than many high-level languages.

If you have more questions, I am here to help 😊

Hi Giant,

It depends on what the author or course means by space complexity.

• Auxiliary space means extra memory the algorithm uses, not counting the input itself.

• Space complexity often means total space used, which can include both input space + auxiliary space.

In many algorithm discussions, people focus on auxiliary space because the input size is usually fixed by the problem, and they want to compare how much extra memory different solutions need.

If you have more questions, I am here to help 😊

Hi Youssef,

An immediate child is an element that is directly inside another element, with nothing in between.

Example:

  
Item