Basic Important Programs

 1)Write a Program to check whether the number is prime (or) not ?

 Input     : 2
 Output  : The 2 is a prime number

 Prime numbers are whole numbers greater than 1 and the number itself.


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2)Write a Program to check whether the number is Palindrome (or) not ?

 Input   : 121
Ouput : It is a Palindrome

A Palindrome is a number which reads the same backward as forward


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3)Write a Program to Reverse  a number ?

 Input      : 123
Ouptut   : 321


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4)Write a Program to find out the sum of digits of a given number ?

 Input      : 123
Output   : 6


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 5)Write a Program to check the number is Armstrong Number (or) not ?

 Input    : 153
Output :  It is a Armstrong Number

 Armstrong Number is a number that is equal to sum of cubes of its digits.


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6)Write a Program to check the number is Strong Number (or) not ?

 Input    : 145
Output : It is a Strong Number

Strong Number is a Special Number whose sum of factorial of digits is equal to the
original number.



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7)Write a Program to Reverse  a String ?

   Input     : raju
 Output   : ujar



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8)Write a Program  to check given string is Palindrome (or) not ?

 Input    : madam
Output : It is a Palindrome 
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9)Write a Program for Fibonacci Series ?

 Input    : 2
Output : 0 1

 A series of numbers in which each number is the sum of the two preceding numbers


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10)Write a Program to print Perfect Number below 500 ?

 Output : 6,28,496

 Perfect Number ,a Positive integer that is equal to the sum of its proper divisors.


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11)Write a Program to implement atoi() function ?

 Input     :  -123@4
Output  :  -123

 atoi converts string to integer.

 int atoi(const char *str);
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12)Write a Program to implement atof() function ?

 Input     : -23.75#4
Output  : -23.750000

 atof converts string to float

 float atof(const char *str);
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