INTRODUCTION TO C PROGRAMMING
Basic c programs
Updated on 31.8.2020
#include<stdio.h>
int main()
{
int n1=0,n2=1,n3,i,number;
printf("Enter the number of elements:");
scanf("%d",&number);
printf("n%d %d",n1,n2);//printing 0 and 1
for(i=2;i<number;++i)/*loop starts from 2 because 0 and 1 are alr
eady printed*/
{
n3=n1+n2;
printf(" %d",n3);
n1=n2;
n2=n3;
}
return 0;
}

#inlcude<stdio.h>
#inlcude<conio.h>
void main()
{
int r=5;
float area;
area=3.14*r*r;
printf("area:%d",area);
getch();
}
BASIC C PROGRAMS
1.Write a program to print the position of the smallestnumber
of n numbers using arrays.
#include <stdio.h>
#include <conio.h>
int main()
{
int i, n, arr[20], small, pos;
clrscr();
printf("n Enter the number of elements in the array : ");
scanf("%d", &n);
printf("n Enter the elements : ");
for(i=0;i<n;i++)
scanf("%d",&arr[i]);

small = arr[0]
pos =0;
for(i=1;i<n;i++)
{
if(arr[i]<small)
{
small = arr[i];
pos = i;
}
}
printf("n The smallest element is : %d", small);
printf("n The position of the smallest element in the array is :
%d", pos);
return 0;
}
2. Write a program to insert a number at a given locationin
an array.
#include <stdio.h>
#include <conio.h>
int main()
{
int i, n, num, pos, arr[10];
clrscr();
printf("n Enter the number of elements in the array : ");
scanf("%d", &n);
for(i=0;i<n;i++)
{
printf("n arr[%d] = ", i);
scanf("%d", &arr[i]);
}
printf("n Enter the number to be inserted : ");
scanf("%d", &num);
printf("n Enter the position at which the number has to be added :
");
scanf("%d", &pos);
for(i=n–1;i>=pos;i––)
arr[i+1] = arr[i];
arr[pos] = num;
n = n+1;
printf("n The array after insertion of %d is : ", num);
for(i=0;i<n;i++)
printf("n arr[%d] = %d", i, arr[i]);
getch();
return 0;
}
Output
Enter the number of elements in the array : 5
arr[0] = 1
arr[1] = 2
arr[2] = 3
arr[3] = 4
arr[4] = 5
Enter the number to be inserted : 0
Enter the position at which the number has to be added : 3
The array after insertion of 0 is :
arr[0] = 1
arr[1] = 2
arr[2] = 3
arr[3] = 0
arr[4] = 4

arr[5] = 5
3.Write a program to insert a number in an array that is
already sortedin ascending order.
#include <stdio.h>
#include <conio.h>
int main()
{
int i, n, j, num, arr[10];
clrscr();
printf("n Enter the number of elements in the array : ");
scanf("%d", &n);
for(i=0;i<n;i++)
{
printf("n arr[%d] = ", i);
scanf("%d", &arr[i]);
}
printf("n Enter the numberto be inserted : ");
scanf("%d", &num);
for(i=0;i<n;i++)
{
if(arr[i] > num)
{
for(j = n–1; j>=i; j––)
arr[j+1] = arr[j];
arr[i] = num;
break;
}
}
n = n+1;
printf("n The array after insertion of %d is : ", num);
for(i=0;i<n;i++)
printf("n arr[%d] = %d", i, arr[i]);
getch();
return 0;
}
Output
Enter the number of elements in the array : 5
arr[0] = 1
arr[1] = 2
arr[2] = 4
arr[3] = 5
arr[4] = 6
Enter the number to be inserted : 3
The array after insertion of 3 is :
arr[0] = 1
arr[1] = 2
arr[2] = 3
arr[3] = 4
arr[4] = 5
arr[5] = 6
4.Write a program to delete a number from a given locationin
an array.
#include <stdio.h>
#include <conio.h>
int main()
{
int i, n, pos, arr[10];
clrscr();
printf("n Enter the number of elements in the array : ");
scanf("%d", &n);

for(i=0;i<n;i++)
{
printf("n arr[%d] = ", i);
scanf("%d", &arr[i]);
}
printf("nEnter the position from which the number has to be
deleted : ");
scanf("%d", &pos);
for(i=pos; i<n–1;i++)
arr[i] = arr[i+1];
n––;
printf("n The array after deletion is : ");
for(i=0;i<n;i++)
printf("n arr[%d] = %d", i, arr[i]);
getch();
return 0;
}
Output
Enter the number of elements in the array : 5
arr[0] = 1
arr[1] = 2
arr[2] = 3
arr[3] = 4
arr[4] = 5
Enter the position from which the number has to be deleted : 3
The array after deletion is :
arr[0] = 1
arr[1] = 2
arr[2] = 3
arr[3] = 5
5. Write a program to merge two unsorted arrays.
#include <stdio.h>
#include <conio.h>
int main()
if(arr1[index_first]<arr2[index_second])
{
arr3[index] = arr1[index_first];
index_first++;
}
else
{
arr3[index] = arr2[index_second];
index_second++;
}
index++;
}
// if elements of the first array are over and the second array has
some elements
if(index_first == n1)
{
while(index_second<n2)
{
arr3[index] = arr2[index_second];
index_second++;
index++;
}
}
// if elements of the second array are over and the first array has
some elements
else if(index_second == n2)
{
while(index_first<n1)
{
arr3[index] = arr1[index_first];

index_first++;
index++;
}
}
printf("nn The merged array is");
for(i=0;i<m;i++)
printf("n arr[%d] = %d", i, arr3[i]);
getch();
return 0;
}
Output
Enter the number of elements in array1 : 3
Enter the elements of the first array
arr1[0] = 1
arr1[1] = 3
arr1[2] = 5
Enter the number of elements in array2 : 3
Enter the elements of the second array
arr2[0] = 2
arr2[1] = 4
arr2[2] = 6
//Program to Printan Integer
#include <stdio.h>
int main() {
int number;
printf("Enter an integer: ");
// reads and stores input
scanf("%d", &number);
// displays output
printf("You entered: %d", number);
return 0;
}
//Program to Add TwoIntegers
#include <stdio.h>
int main() {
int number1, number2, sum;
printf("Enter two integers: ");
scanf("%d %d", &number1, &number2);
// calculating sum
sum = number1 + number2;
printf("%d + %d = %d", number1, number2, sum);
return 0;
}
//Program to Multiply Two Numbers
#include <stdio.h>
int main() {
double a, b, product;
printf("Enter two numbers: ");

scanf("%lf %lf", &a, &b);
// Calculating product
product= a * b;
// Result up to 2 decimal point is displayed using %.2lf
printf("Product = %.2lf", product);
return 0;
}
//Swap Numbers Using Temporary Variable
#include<stdio.h>
int main() {
double first, second, temp;
printf("Enter first number: ");
scanf("%lf", &first);
printf("Enter second number: ");
scanf("%lf", &second);
// Value of first is assigned to temp
temp = first;
// Value of second is assigned to first
first = second;
// Value of temp (initial value of first) is assigned to second
second = temp;
printf("nAfter swapping, firstNumber = %.2lfn", first);printf("After swapping, secondNumber = %.2lf", second);
return 0;
}
Programto Check Vowelor consonant
#include <stdio.h>
int main() {
char c;
int lowercase_vowel, uppercase_vowel;
printf("Enter an alphabet: ");
scanf("%c", &c);
// evaluates to 1 if variable c is a lowercase vowel
lowercase_vowel = (c == 'a' || c == 'e' || c == 'i' || c == 'o' || c ==
'u');
// evaluates to 1 if variable c is a uppercasevowel
uppercase_vowel= (c == 'A' || c == 'E' || c == 'I' || c == 'O' || c
== 'U');
// evaluates to 1 (true) if c is a vowel
if (lowercase_vowel || uppercase_vowel)
printf("%c is a vowel.", c);
else
printf("%c is a consonant.", c);
return 0;

}
Check Armstrong Number of three digits
//153 = 1*1*1 + 5*5*5 + 3*3*3
#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;
}
#include <stdio.h>
int main() {
int num, originalNum, remainder, result = 0;
printf("Enter a three-digit integer: ");
scanf("%d", &num);
originalNum = num;
while (originalNum != 0) {
// remainder contains the last digit
remainder = originalNum % 10;
result += remainder * remainder * remainder;
// removing last digit from the orignal number
originalNum /= 10;}
if (result == num)
printf("%d is an Armstrong number.", num);
else
printf("%d is not an Armstrong number.", num);
return 0;
}
Programto Check Palindrome
#include <stdio.h>
int main() {
int n, reversedN = 0, remainder, originalN;
printf("Enter an integer: ");
scanf("%d", &n);
originalN = n;
// reversed integer is stored in reversedN
while (n != 0) {
remainder = n % 10;
reversedN = reversedN * 10 + remainder;
n /= 10;
}
// palindrome if originalN and reversedN are equal
if (originalN == reversedN)
printf("%d is a palindrome.", originalN);
else

printf("%d is not a palindrome.", originalN);
return 0;
}
//ARRAY
//Example 2: Sum of two matrices
// C program to find the sum of two matrices of order 2*2
#include <stdio.h>
int main()
{
float a[2][2], b[2][2], result[2][2];
// Taking input using nested for loop
printf("Enter elements of 1st matrixn");
for (int row = 0; row < 2; ++row)
for (int col= 0; col< 2; ++col)
{
printf("Enter a%d%d:", row + 1, col+ 1);
scanf("%f", &a[row][col]);
}
// Taking input using nested for loop
printf("Enter elements of 2nd matrixn");
for (int row = 0; row < 2; ++row)
for (int col= 0; col< 2; ++col)
{
printf("Enter b%d%d:", row + 1, col+ 1);
scanf("%f", &b[row][col]);
}
// adding correspondingelements of two arrays
for (int row = 0; row < 2; ++row)
for (int col= 0; col< 2; ++col)
{
result[row][col] = a[row][col] + b[row][col];
}
// Displaying the sum
printf("nSum Of Matrix:");
for (int row = 0; row < 2; ++row)
for (int col= 0; col< 2; ++col)
{
printf("%.1ft", result[row][col]);
if (col == 1)
printf("n");
}
return 0;
}

Program to Find the Transpose of a
Matrix
#include <stdio.h>
int main() {
int a[10][10], transpose[10][10], r, c, i, j;
printf("Enter rows and columns: ");
scanf("%d %d", &r, &c);
// Assigning elements to the matrix
printf("nEnter matrix elements:n");
for (i = 0; i < r; ++i)
for (j = 0; j < c; ++j) {
printf("Enter element a%d%d: ", i + 1, j + 1);
scanf("%d", &a[i][j]);
}
// Displaying the matrix a[][]
printf("nEntered matrix: n");
for (i = 0; i < r; ++i)
for (j = 0; j < c; ++j) {
printf("%d ", a[i][j]);
if (j == c - 1)
printf("n");
}
// Finding the transpose of matrix a
for (i = 0; i < r; ++i)
for (j = 0; j < c; ++j) {transpose[j][i] = a[i][j];
}
// Displaying the transpose of matrix a
printf("nTranspose of the matrix:n");
for (i = 0; i < c; ++i)
for (j = 0; j < r; ++j) {
printf("%d ", transpose[i][j]);
if (j == r - 1)
printf("n");
}
return 0;
}