This document contains 3 examples of C programming code that demonstrate working with arrays: 1) Printing the reverse of user-input numbers in an array, 2) Separating even and odd numbers from an array into two new arrays, and 3) Merging and sorting two arrays of user-input numbers in descending order into a third array. Each example provides the full code, input/output examples, and brief descriptions to demonstrate array manipulation techniques in C.

1. C Programming Examples
-R.Sandhiya,
AP/CIT

2. Arrays
2

3. 1. Example to print
reverse of n numbers
3

4. “
#include <stdio.h>
void main()
{
int i,n,a[100];
printf("nnRead n number of values in an array and display it in
reverse order:n");
printf("Input the number of elements to store in the array :");
scanf("%d",&n);
printf("Input %d number of elements in the array :n",n);
for(i=0;i<n;i++)
{
printf("element - %d : ",i);
scanf("%d",&a[i]);
}
4

5. “ printf("nThe values stored into the array are : n");
for(i=0;i<n;i++)
{
printf("%d",a[i]);
}
printf("nnThe values store into the array in reverse are :n");
for(i=n-1;i>=0;i--)
{
printf("%d",a[i]);
}
printf("nn");
}
5

6. 2. Example to separate
odd and even integers
and display in separate
arrays
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7. 7

8. 8
#include <stdio.h>
void main()
{
int arr1[10], arr2[10], arr3[10];
int i,j=0,k=0,n;
printf("Input the number of elements to be stored in the array :");
scanf("%d",&n);
printf("Input %d elements in the array :n",n);
for(i=0;i<n;i++)
{
printf("element - %d : ",i);
scanf("%d",&arr1[i]);
}

9. 9
for(i=0;i<n;i++)
{
if (arr1[i]%2 == 0)
{
arr2[j] = arr1[i];
j++;
}
else
{
arr3[k] = arr1[i];
k++;
}
}

10. 10
printf("nThe Even elements are : n");
for(i=0;i<j;i++)
{
printf("%d ",arr2[i]);
}
printf("nThe Odd elements are :n");
for(i=0;i<k;i++)
{
printf("%d ", arr3[i]);
}
printf("nn");
}

11. 11
Input the number of elements to be stored in the array
:5
Input 5 elements in the array :
element - 0 : 25
element - 1 : 47
element - 2 : 42
element - 3 : 56
element - 4 : 32
The Even elements are :
42 56 32
The Odd elements are :
25 47

12. 3. Example to merge and
sort numbers in
descending order
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13. 13

14. 14
#include <stdio.h>
void main()
{
int arr1[100], arr2[100], arr3[200];
int s1, s2, s3;
int i, j, k;
printf("nnMerge two arrays of same size sorted in decending order.n");
printf("Input the number of elements to be stored in the first array :");
scanf("%d",&s1);
printf("Input %d elements in the array :n",s1);
for(i=0;i<s1;i++)
{
printf("element - %d : ",i);
scanf("%d",&arr1[i]);
}

15. 15
printf("Input the number of elements to be stored in the second array :");
scanf("%d",&s2);
printf("Input %d elements in the array :n",s2);
for(i=0;i<s2;i++)
{
printf("element - %d : ",i);
scanf("%d",&arr2[i]);
}
/* size of merged array is size of first array and size of second array */
s3 = s1 + s2;

16. 16
/*----------------- insert in the third array------------------------------------*/
for(i=0;i<s1; i++)
{
arr3[i] = arr1[i];
}
for(j=0;j<s2; j++)
{
arr3[i] = arr2[j];
i++;
}

17. 17
/*----------------- sort the array in decending order ---------------------------*/
for(i=0;i<s3; i++)
{
for(k=0;k<s3-1;k++)
{
if(arr3[k]<=arr3[k+1])
{
j=arr3[k+1];
arr3[k+1]=arr3[k];
arr3[k]=j;
}
}
}

18. 18
/*--------------- Prints the merged array ------------------------------------*/
printf("nThe merged array in decending order is :n");
for(i=0; i<s3; i++)
{
printf("%d ", arr3[i]);
}
printf("nn");
}

19. 19
Merge two arrays of same size sorted in decending order.
Input the number of elements to be stored in the first array :3
Input 3 elements in the array :
element - 0 : 1
element - 1 : 2
element - 2 : 3
Input the number of elements to be stored in the second array :3
Input 3 elements in the array :
element - 0 : 1
element - 1 : 2
element - 2 : 3
The merged array in decending order is : 3 3 2 2 1 1

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THANKS!
You can find me at:
▪ rsandhiya@cit.edu.in