The document contains a comprehensive collection of C programming exercises, covering various fundamental concepts such as checking even or odd numbers, finding the largest number among three inputs, and determining leap years. Each exercise is accompanied by source code and outputs, serving as practical examples for learning C programming. It also includes recursive solutions for problems like calculating the sum of natural numbers and finding factorials.

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C Programming 28 Program
Table of Contents
Page no
1) C Program to Check Whether a Number is Even or Odd...................................................................................................12
2) C Program to Check Whether a Character is Vowel or Consonant ........................................................................................22
3) C Program to Find the Largest Number Among Three Numbers .......................................................................................33
4) C Program to Check Leap Year ....................................................................................................................................................45
5) C Program to Check Whether a Number is Positive or Negative ...........................................................................................55
6) C Program to Check Whether a Character is an Alphabet or not ......................................................................................66
7 ) C Program to Generate Multiplication Table ....................................................................................................................77
8 ) C Program to Display Fibonacci Sequence .........................................................................................................................88
9 ) C Program to Find GCD of two Numbers............................................................................................................................99
10 ) C Program to Find LCM (Lowest Common Multiple) of two Number ...........................................................................101
11) C Program to Display Characters from A to Z Using Loop ..............................................................................................111
12) C Program to Reverse a Number.....................................................................................................................................122
13 ) C Program to Calculate the Power of a Number............................................................................................................133
14) C Program to Check Whether a Number is Palindrome or Not......................................................................................144
15) C Program to Check Whether a Number is Prime or Not...............................................................................................155
16) C Program to Display Prime Numbers Between Two Intervals......................................................................................166
17 ) C Program to Check Armstrong Number........................................................................................................................177
18) C Program to Display Factors of a Number.....................................................................................................................188
19) C Programming Code To Create Pyramid and Pattern ...................................................................................................199
20) C Program to Make a Simple Calculator Using switch...case .........................................................................................200
21) C Programming Code To Create Pyramid and Pattern ...................................................................................................211
22) C Program to Display Prime Numbers Between Intervals Using Function ....................................................................222
23) C Program to Check Prime or Armstrong Number Using User-defined Function..........................................................233
24) C Program to Find the Sum of Natural Numbers using Recursion .................................................................................255
25) C Program to Find Factorial of a Number Using Recursion ...........................................................................................266
26) C Program to Find G.C.D Using Recursion.......................................................................................................................277
27) C program to Reverse a Sentence Using Recursion........................................................................................................288
28) C program to calculate the power using recursion.........................................................................................................299

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1) C Program to Check Whether a Number is Even or Odd
#include <stdio.h>
int main()
{
int number;
printf("Enter an integer: ");
scanf("%d", &number);
if(number % 2 == 0)
printf("%d is even.", number);
else
printf("%d is odd.", number);
return 0;
}
Output

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2) C Program to Check Whether a Character is Vowel or Consonant
#include <stdio.h>
int main()
{
char c;
int isLowercaseVowel, isUppercaseVowel;
printf("Enter an alphabet: ");
scanf("%c",&c);
isLowercaseVowel = (c == 'a' || c == 'e' || c == 'i' || c == 'o' || c == 'u');
isUppercaseVowel = (c == 'A' || c == 'E' || c == 'I' || c == 'O' || c == 'U');
if (isLowercaseVowel || isUppercaseVowel)
printf("%c is a vowel.", c);
else
printf("%c is a consonant.", c);
return 0;
}
Output

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3) C Program to Find the Largest Number Among Three Numbers
#include <stdio.h>
int main()
{
double n1, n2, n3;
printf("Enter three numbers: ");
scanf("%lf %lf %lf", &n1, &n2, &n3);
if( n1>=n2 && n1>=n3)
printf("%.2lf is the largest number.", n1);
else if (n2>=n1 && n2>=n3)
printf("%.2lf is the largest number.", n2);
else
printf("%.2lf is the largest number.", n3);
return 0;
}
Output

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4) C Program to Check Leap Year
#include <stdio.h>
int main()
{
int year;
printf("Enter year : ");
scanf("%d", &year);
if(((year % 4 == 0) && (year % 100 !=0)) || (year % 400==0))
{
printf("LEAP YEAR");
}
else
{
printf("COMMON YEAR");
}
return 0;
}
Output

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5) C Program to Check Whether a Number is Positive or Negative
#include <stdio.h>
int main()
{
double number;
printf("Enter a number: ");
scanf("%lf", &number);
if (number < 0.0)
printf("You entered a negative number.");
else if ( number > 0.0)
printf("You entered a positive number.");
else
printf("You entered 0.");
return 0;
}
Output

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6) C Program to Check Whether a Character is an Alphabet or not
#include <stdio.h>
int main()
{
char c;
printf("Enter a character: ");
scanf("%c",&c);
if( (c>='a' && c<='z') || (c>='A' && c<='Z'))
printf("%c is an alphabet.",c);
else
printf("%c is not an alphabet.",c);
return 0;
}
Output

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7 ) C Program to Generate Multiplication Table
#include <stdio.h>
int main()
{
int n, i;
printf("Enter an integer: ");
scanf("%d",&n);
for(i=1; i<=10; ++i)
{
printf("%d * %d = %d n", n, i, n*i);
}
return 0;
}
Output

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8 ) C Program to Display Fibonacci Sequence
#include <stdio.h>
int main()
{
int i, n, t1 = 0, t2 = 1, nextTerm;
printf("Enter the number of terms: ");
scanf("%d", &n);
printf("Fibonacci Series: ");
for (i = 1; i <= n; ++i)
{
printf("%d, ", t1);
nextTerm = t1 + t2;
t1 = t2;
t2 = nextTerm;
}
return 0;
}

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9 ) C Program to Find GCD of two Numbers
#include <stdio.h>
int main()
{
int n1, n2, i, gcd;
printf("Enter two integers: ");
scanf("%d %d", &n1, &n2);
for(i=1; i <= n1 && i <= n2; ++i)
{
if(n1%i==0 && n2%i==0)
gcd = i;
}
printf("G.C.D of %d and %d is %d", n1, n2, gcd);
return 0;
}
Output

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10 ) C Program to Find LCM (Lowest Common Multiple) of two Numbers
#include <stdio.h>
int main()
{
int n1, n2, i, gcd, lcm;
printf("Enter two positive integers: ");
scanf("%d %d",&n1,&n2);
for(i=1; i <= n1 && i <= n2; ++i)
{
if(n1%i==0 && n2%i==0)
gcd = i;
}
lcm = (n1*n2)/gcd;
printf("The LCM of two numbers %d and %d is %d.", n1, n2, lcm);
return 0;
}
Output

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11) C Program to Display Characters from A to Z Using Loop
#include <stdio.h>
int main()
{
char c;
for(c = 'A'; c <= 'Z'; ++c)
printf("%c ", c);
return 0;
}
Output

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12) C Program to Reverse a Number
#include <stdio.h>
int main()
{
int n, reverse = 0;
printf("Enter a number to reversen");
scanf("%d", &n);
while (n != 0)
{
reverse = reverse * 10;
reverse = reverse + n%10;
n = n/10;
}
printf("Reverse of entered number is = %dn", reverse);
return 0;
}
Output

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13 ) C Program to Calculate the Power of a Number
#include <stdio.h>
int main()
{
int base, exponent;
long long result = 1;
printf("Enter a base number: ");
scanf("%d", &base);
printf("Enter an exponent: ");
scanf("%d", &exponent);
while (exponent != 0)
{
result *= base;
--exponent;
}
printf("Answer = %lld", result);
return 0;
}
Output

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14) C Program to Check Whether a Number is Palindrome or Not
#include <stdio.h>
int main()
{
int n, reversedInteger = 0, remainder, originalInteger;
printf("Enter an integer: ");
scanf("%d", &n);
originalInteger = n;
while( n!=0 )
{
remainder = n%10;
reversedInteger = reversedInteger*10 + remainder;
n /= 10;
}
if (originalInteger == reversedInteger)
printf("%d is a palindrome.", originalInteger);
else
printf("%d is not a palindrome.", originalInteger);
return 0;
}
Output

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15) C Program to Check Whether a Number is Prime or Not
#include <stdio.h>
int main()
{
int n, i, flag = 0;
printf("Enter a positive integer: ");
scanf("%d", &n);
for(i = 2; i <= n/2; ++i)
{
if(n%i == 0)
{
flag = 1;
break;
}
}
if (n == 1)
{
printf("1 is neither a prime nor a composite number.");
}
else
{
if (flag == 0)
printf("%d is a prime number.", n);
else
printf("%d is not a prime number.", n);
}
return 0;
} Output

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16) C Program to Display Prime Numbers Between Two Intervals
#include <stdio.h>
int main()
{
int low, high, i, flag;
printf("Enter two numbers(intervals): ");
scanf("%d %d", &low, &high);
printf("Prime numbers between %d and %d are: ", low, high);
while (low < high)
{
flag = 0;
for(i = 2; i <= low/2; ++i)
{
if(low % i == 0)
{
flag = 1;
break;
}
}
if (flag == 0)
printf("%d ", low);
++low;
}
return 0;
} Output

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17 ) C Program to Check Armstrong Number
#include <stdio.h>
int main()
{
int number, originalNumber, remainder, result = 0;
printf("Enter a three digit integer: ");
scanf("%d", &number);
originalNumber = number;
while (originalNumber != 0)
{
remainder = originalNumber%10;
result += remainder*remainder*remainder;
originalNumber /= 10;
}
if(result == number)
printf("%d is an Armstrong number.",number);
else
printf("%d is not an Armstrong number.",number);
return 0;
}
Output

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18) C Program to Display Factors of a Number
#include <stdio.h>
int main()
{
int number, i;
printf("Enter a positive integer: ");
scanf("%d",&number);
printf("Factors of %d are: ", number);
for(i=1; i <= number; ++i)
{
if (number%i == 0)
{
printf("%d ",i);
}
}
return 0;
}
Output

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19) C Programming Code To Create Pyramid and Pattern
#include <stdio.h>
int main()
{
int i, j, rows;
printf("Enter number of rows: ");
scanf("%d",&rows);
for(i=1; i<=rows; ++i)
{
for(j=1; j<=i; ++j)
{
printf("* ");
}
printf("n");
}
return 0;
} Output

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20) C Program to Make a Simple Calculator Using switch...case
# include <stdio.h>
int main() {
char operator;
double firstNumber,secondNumber;
printf("Enter an operator (+, -, *,): ");
scanf("%c", &operator);
printf("Enter two operands: ");
scanf("%lf %lf",&firstNumber, &secondNumber);
switch(operator)
{
case '+':
printf("%.1lf + %.1lf = %.1lf",firstNumber, secondNumber, firstNumber + secondNumber);
break;
case '-':
printf("%.1lf - %.1lf = %.1lf",firstNumber, secondNumber, firstNumber - secondNumber);
break;
case '*':
printf("%.1lf * %.1lf = %.1lf",firstNumber, secondNumber, firstNumber * secondNumber);
break;
case '/':
printf("%.1lf / %.1lf = %.1lf",firstNumber, secondNumber, firstNumber / secondNumber);
break;
default:
printf("Error! operator is not correct");
}
return 0; Output
}

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21) C Programming Code To Create Pyramid and Pattern
#include <stdio.h>
int main()
{
int i, space, rows, k=0;
printf("Enter number of rows: ");
scanf("%d",&rows);
for(i=1; i<=rows; ++i, k=0)
{
for(space=1; space<=rows-i; ++space)
{
printf(" ");
}
while(k != 2*i-1)
{
printf("* ");
++k;
}
printf("n");
}
return 0;
}
Output

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22) C Program to Display Prime Numbers Between Intervals Using Function
#include <stdio.h>
int checkPrimeNumber(int n);
int main()
{
int n1, n2, i, flag;
printf("Enter two positive integers: ");
scanf("%d %d", &n1, &n2);
printf("Prime numbers between %d and %d are: ", n1, n2);
for(i=n1+1; i<n2; ++i)
{
flag = checkPrimeNumber(i);
if(flag == 1)
printf("%d ",i);
}
return 0;
}
int checkPrimeNumber(int n)
{
int j, flag = 1;
for(j=2; j <= n/2; ++j)
{
if (n%j == 0)
{
flag =0;
break;
}
} Output
return flag;
}

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23) C Program to Check Prime or Armstrong Number Using User-defined Function
#include <stdio.h>
#include <math.h>
int checkPrimeNumber(int n);
int checkArmstrongNumber(int n);
int main()
{
int n, flag;
printf("Enter a positive integer: ");
scanf("%d", &n);
flag = checkPrimeNumber(n);
if (flag == 1)
printf("%d is a prime number.n", n);
else
printf("%d is not a prime number.n", n);
flag = checkArmstrongNumber(n);
if (flag == 1)
printf("%d is an Armstrong number.", n);
else
printf("%d is not an Armstrong number.",n);
return 0;
}
int checkPrimeNumber(int n)
{
int i, flag = 1;
for(i=2; i<=n/2; ++i)
{
if(n%i == 0)
{
flag = 0;
break;

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}
}
return flag;
}
int checkArmstrongNumber(int number)
{
int originalNumber, remainder, result = 0, n = 0, flag;
originalNumber = number;
while (originalNumber != 0)
{
originalNumber /= 10;
++n;
}
originalNumber = number;
while (originalNumber != 0)
{
remainder = originalNumber%10;
result += pow(remainder, n);
originalNumber /= 10;
}
if(result == number)
flag = 1;
else
flag = 0;
return flag;
}
Output

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24) C Program to Find the Sum of Natural Numbers using Recursion
#include <stdio.h>
int addNumbers(int n);
int main()
{
int num;
printf("Enter a positive integer: ");
scanf("%d", &num);
printf("Sum = %d",addNumbers(num));
return 0;
}
int addNumbers(int n)
{
if(n != 0)
return n + addNumbers(n-1);
else
return n;
}
Output

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25) C Program to Find Factorial of a Number Using Recursion
#include <stdio.h>
long int multiplyNumbers(int n);
int main()
{
int n;
printf("Enter a positive integer: ");
scanf("%d", &n);
printf("Factorial of %d = %ld", n, multiplyNumbers(n));
return 0;
}
long int multiplyNumbers(int n)
{
if (n >= 1)
return n*multiplyNumbers(n-1);
else
return 1;
}
Output

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26) C Program to Find G.C.D Using Recursion
#include <stdio.h>
int hcf(int n1, int n2);
int main()
{
int n1, n2;
printf("Enter two positive integers: ");
scanf("%d %d", &n1, &n2);
printf("G.C.D of %d and %d is %d.", n1, n2, hcf(n1,n2));
return 0;
}
int hcf(int n1, int n2)
{
if (n2 != 0)
return hcf(n2, n1%n2);
else
return n1;
}
Output

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27) C program to Reverse a Sentence Using Recursion
#include <stdio.h>
void reverseSentence();
int main()
{
printf("Enter a sentence: ");
reverseSentence();
return 0;
}
void reverseSentence()
{
char c;
scanf("%c", &c);
if( c != 'n')
{
reverseSentence();
printf("%c",c);
}
}
Output

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28) C program to calculate the power using recursion
#include <stdio.h>
int power(int n1, int n2);
int main()
{
int base, powerRaised, result;
printf("Enter base number: ");
scanf("%d",&base);
printf("Enter power number(positive integer): ");
scanf("%d",&powerRaised);
result = power(base, powerRaised);
printf("%d^%d = %d", base, powerRaised, result);
return 0;
}
int power(int base, int powerRaised)
{
if (powerRaised != 0)
return (base*power(base, powerRaised-1));
else
return 1;
}
Output

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-: THE END :-