C Language Tutorial on Conditional Statements for Beginners Session - 4 Video Lecture | Basics of C Language - Fundamentals of Programming - Software Development

c language session for in session for
will be taking up conditional statements
that is conditional statements are used
for decision-making like true or false
based on a given condition the compiler
will decide to execute a particular task
or to skip that particular task this is
called as conditional statements the
syntax the very first conditional
statement for a phase if the condition
or expression will be giving up certain
condition in the set of braces this we
call as if condition if this is true it
will execute the statement or statements
for example hash include stdio.h a main
function now in this say in de jure a
comma B scan for the prompt the user so
that he could enter some values enter
numbers the scan certain values person d
for both ampersand a coma I ampersand be
now here after getting the values see if
if a greater than B is this is true then
print is big okay now say control f9 to
see the output because of scanf again
it's asking the values let for a it be
78 and 4b it be 23 is it not 78 greater
than B and so because this is true I
will be executing the printf statement
is Vic the output happens to be 10
the value is given by user are 45 45 and
99 what do you say 45 greater than 99 is
absolutely false and so I won't execute
the printf statement so whenever this
condition is true we'll execute the
printer for whatever it may be whenever
the condition is false we'll skip this
block we call this block as if block so
based on the condition will be executing
the if block or will be skipping the
f-block the next one is else block if
else statement to a branching now it's
clear that if the condition is false we
are skipping this entire if block if
this is false then the compiler will go
for else block seeing printf if a is not
big then the other thing can be B is big
now again check for the output if your
inputs are 45 and 30 345 is greater than
33 as this is true i will be printing a
is big if my inputs now are 56 56 and 89
56 is greater than 89 is absolutely
false now comes the else block into play
printing B is big so when the condition
is true will enter into if block when
the condition is false we'll skip the if
block and will take up else block so it
is either if block or
else block anyone but not both the same
example over here FL statement to we're
branching if a greater than B you will
be saying a greater than B if this is
false come to a block saying is less
than B the taking of few more examples
over here this is a program with which
you can find out which is a highest
given between two numbers going for
another program a main function in which
I take up value let the variable name
being number so printf enter a number
for users prompting sake scanf person
tacoma ampersand number now because of
scanners will get an input if a
condition in the set of braces that will
see like my requirement in this program
is to say whether the given number into
the variable number is a even number or
odd number so mathematical logic for
even number happens to be if consider
it's 33 when you divide 33 by 2 if your
reminder is 0 33 is an even number but
in fact the reminder we get when we
divide 33 x 2 is one so it's odd number
so what I say the condition is the
number which can be anything and I am
speaking about reminder we have the
percentile operator the reminder what i
get when i divide with 2 is it the same
as 0 consider it is 32 32 percentile to
yes 32 / 2 reminder is
you know yes this is true so printf
person d is even if not comes to else
block printf person d is odd now
consider my input is 32 32 because when
you divide 32 x to the reminder you get
is 0 is it not the same I am comparing
over here and hansel print 32 easy one
if my input is now 45 45 45 / to the
percentile that is the reminder what we
get is it 0 it's one actually now this
entire if condition is false when the
condition is false we'll be coming to
else block printing percent is that is
45 is odd so in this way using an if
condition we can say whether the given
number is even or odd this condition is
specially used in making certain
decision whether this then do then
execute Dave block if the condition
given over here is true execute the if
block if the condition given over here
is false execute the else block one more
example an integer variable i is 10
comma j is 20 if I less than J which is
true absolutely true and I want to
execute if block
as you know the output is F block
because the condition is absolutely true
if I want to execute more than two
statements under F block right those two
statements in a set of statements
another statement executes these two
statements in a set of block now
compiler treats both the statements as
one based on the condition compiler will
decide whether to execute the state two
statements or whether to skip the two
statements as of now this is a true
condition so it will give if another if
block and another statement as your
output going for another program now
this is a program with which we can find
out the given year is it a leap year or
not so include the header file stdio.h
main integer year is a variable name so
printf entera year scanf person d comma
ampersand here now before going for the
condition first of all how will we
decide whether the given here is a leap
year or not consider the case 2000 that
is a leap year because 2000 is divisible
by four as well as 400 and consider an
ear like 1984 1984 is divisible by four
but not divisible by 2 400 so for leepy
especially for leap years if it is
divisible by 400 that is a leap year and
normally yes if the normal ear is
divisible by four it is a leap year
apart from these if we get any other
year which comes out of these things it
is considered as a non leap here
so the condition happens to be if year
percentile the reminder when you divide
it with four is it same as 0 or year
percentile 400 when you divide the year
with 400 is it same as 0 if these two
and the logical an ear percentile 100
not equal to 0 then you can consider it
as a leap year person d is a leap year
if not printf person d is not a live
here now execute the program let the
year be two hundred two thousand two
thousand is a leap year because two
thousand is divisible by four actually
when it comes to centuries the centuries
should be divisible by 400 strictly four
hundred can do I two thousand and so
this entire condition happens to be true
I am executing 2000 is a live here
consider one more input this time the
input is 1900 does 1900 divisible by 400
so considering 1,900 1,900 is not a leap
year and one more year like 1984 which
is a leap year so the leap leap year
statement happens to be when a year is
divisible by four it is considered as a
leap year if it's not divisible
why for it's not considered as a leap
year and coming two centuries it should
be divisible by 400 whereas 1900 is not
divisible by 400 and so we don't
consider as 1900 as a leap year coming
to the other sections of if block is
hash include stdio dot H a main function
in which I say I will receive the marks
were subject 1 comma subject to come a
subject 3 a float variable with name avg
in which I place the average of s1 plus
s2 plus s 3 by 3 so s1 plus s2 plus s3
add them first of all and divide by
three with this will get the average now
if average is greater than or equal to
60 we can directly say printf first
class if average is less than or let me
say is greater than or equal to now if
average its if it's greater than six
hits first class if average is greater
than 45 let me say 45 and average is
less than or equal to 15 9 greater than
or equal to 45 and less than or equal to
59 then we can say printf second class
if average is greater than or equal to
35 and average is less than or equal to
44 then we can print third class if
average is less than 35 then we can
print fail now give the inputs
give the inputs let it be 60 60 and 60
so its first class now let the inputs be
50 50 50 its second plus and now let me
give the inputs as 40 40 and 40 so its
third plus if my inputs are less than 35
the average let it be 34 34 at 34 so
it's a failure so in this way we can use
if-else conditions with which we can
decide whether to take up this block or
to go for as block strictly based on the
condition we will take up furthermore if
else conditions we could calling as
nested if block in the next session