Lecture 2: Write Your First Program in C++
This is the 2nd lecture of our DSA series. We will see how a program runs
and what does each line mean in this lecture. This is how the compilation
process work So it is compiler which makes it possible for us to run a source
code. Coding Ninjas has supported us in providing this amazing DSA course
to you. Courses are available in both Hindi and English. you need an IDE to
write, run and execute a code. There are many IDEs out there - CodeBlocks,
VsCode and many more - which you do n't even need to install Replit is one
of them. You can directly create a C++ there and run it using Replit. In C++,
many namespaces are there which have cout functions in them so if we
want to use cout , we have to add this file to our code. We use these signs
to output the result into standard namespace. If you will use > > by mistake
by mistake, then it will give you compilation error So we use this operator
to display output.
We are going to talk about data types and variables. Whenever you have to
story any information or data in the memory. You have to mention what
type of data it is and how much memory it will take. For eg- int a = 5, a is a
variable in memory which is of int type and it has value 5 in it. We have
certain rules which we have to follow when we are giving names. There is a
function named sizeof , which will tell you about the space being used by
any variable. In memory, first 29 bits will have 0, and last 3 bits will be 101,
so in memory the first 29 bit will have 0 and the last 3bits will have 101. We
have a way to story multiple characters but we will see that in upcoming
lectures. In c++, all the characters are mapped to some ASCII value in
memory. We will just store binary form of ASCII value of any character. If
we have 4 different bytes with some binary value, how will compiler know
whether it is a single Int value of 4 separate char values ? Compiler will
come to know from data types which we used when we declared any
variable. This process of converting one data type into another is known as
1
This is the 2nd lecture of our DSA series. We will see how a program runs
and what does each line mean in this lecture. This is how the compilation
process work So it is compiler which makes it possible for us to run a source
code. Coding Ninjas has supported us in providing this amazing DSA course
to you. Courses are available in both Hindi and English. you need an IDE to
write, run and execute a code. There are many IDEs out there - CodeBlocks,
VsCode and many more - which you do n't even need to install Replit is one
of them. You can directly create a C++ there and run it using Replit. In C++,
many namespaces are there which have cout functions in them so if we
want to use cout , we have to add this file to our code. We use these signs
to output the result into standard namespace. If you will use > > by mistake
by mistake, then it will give you compilation error So we use this operator
to display output.
We are going to talk about data types and variables. Whenever you have to
story any information or data in the memory. You have to mention what
type of data it is and how much memory it will take. For eg- int a = 5, a is a
variable in memory which is of int type and it has value 5 in it. We have
certain rules which we have to follow when we are giving names. There is a
function named sizeof , which will tell you about the space being used by
any variable. In memory, first 29 bits will have 0, and last 3 bits will be 101,
so in memory the first 29 bit will have 0 and the last 3bits will have 101. We
have a way to story multiple characters but we will see that in upcoming
lectures. In c++, all the characters are mapped to some ASCII value in
memory. We will just store binary form of ASCII value of any character. If
we have 4 different bytes with some binary value, how will compiler know
whether it is a single Int value of 4 separate char values ? Compiler will
come to know from data types which we used when we declared any
variable. This process of converting one data type into another is known as
1
