1. C Programming
Language
By:
Yogendra Pal
yogendra@learnbywatch.com
Dedicated to My mother and Father

2. t
y
Keep your notebook with you.
Write important point and questions that comes in your mind
Solve Mind band exercise.
C
Rewind when not clear
Ask Questions by call or SMS or by mail
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THIS IS LOOPS
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3. Need
• Consider a problem:
– Write a program that print “Hello” 5 times.
– One possible statement to solve this problem is :
• printf(“Hello n Hello n Hello n Hello n Hello);
– But what if we want to print “Hello” 1000 times?
– We need a control structure that repeatedly execute
the following statement.
• printf(“n Hello);

4. Decision statements
• To change the control flow of a program we
use:
– Branching statements : cause one section of code
to be executed or not executed, depending on a
conditional clause.
– Looping statements : used to repeat a section of
code a number of times or until some condition
occurs.

5. Looping Statements
• Allow the program to repeat a section of code
any number of times untill some condition
occures.

6. Looping statements : 1
• while statement
initial_statement;
– General form: while(condition){
statement;
while(condition) iteration_statement;
statement; }
• The program will repeatedly execute the
statement inside the while until the condition
becomes false (0)

7. Problems
• Write a program that print “Hello” 5 times.
while(counter <= 5)
printf(“Hello”);
• This statement reads
– “while counter is less than or equal to 5 print Hello ”

8. Multiple Statements
• Put all statements inside the curly { } braces.
while(condition)
{
statement 1;
statement 2;
statement 3;
}

9. (I ++) or (++ I)
• while (i++ < 10)
– compare i with 10,
– increment i.
• while (++i < 10)
– increment i,
– compare i with 10.

10. Problems
• Write a program that print numbers from 1 to 100.
• Write a program that print sum of 10 consecutive
numbers, enter first number using keyboard.
• Write a program that print all even numbers from
1 to 100.
• Write a program to find the factorial value of any
number entered through the keyboard.

11. break statement
• break statement:
– Loops can be exited at any point through the use of
a break statement.
• Write a program that checks whether a given
number is prime of not.

12. continue statement
• continue statement:
– continue starts re-executing the body of the loop
from the top.
• Write a program that print numbers from 1 to 100
except the numbers that are divisible by 5 using
continue statement.

13. Nested while
while(condition) while(condition)
while(condition) {
statement; while(condition)
{
statement;
while(condition) }
{ }
if(condition)
statement;
else
statement;
}

14. Mind Bend
Write a program that print all the numbers
from 2 to 100 with the indication whether a
number is prime of not.
Output will be like:
2 : prime
3 : prime
4 : not prime

15. Looping Statement : 2
• for statement
• General form:
for (initial_statement; condition; iteration_statement)
body_statement;
initial_statement;
while(condition){
statement;
iteration_statement;
}

16. Problems
• Two numbers (x and y) are entered through
the keyboard. Write a program to find the
value of xy
• Write a program that print numbers from 1
to 100 except the numbers that are divisible
by 5 and 7.
• Write a program to print all characters with
their ASCII value.
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17. Looping Statement : 3
• do-while loop
do{
statement1;
statement2
}while(condition)
• do-while run the statements at least once.

18. Problems
• Write a program that first take two numbers
from user and then one operator (+, -, *, /, %)
and print the result accordingly.
• Now modify the above program that give an
option to the user to repeat the operation
again and again with different operator
choosen by him.

19. Mind Bend
• Write a program that takes 10 floating-point
numbers as a input from user and print the
greatest number.
• Write a program that take floating point
number from user and print
– ICE if it is less than 0.
– WATER if it lies between 0 and 100.
– STEAM if it is greater then 100.
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20. To get complete benefit of this tutorial solve all the quiz on
www.learnbywatch.com
For any problem in this tutorial mail me at
yogendra@learnbywatch.com
with the subject “C”
For Other information mail at
info@learnbywatch.com
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NEXT IS FUNCTIONS
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