C Program to Find Ceiling and Floor Value of Sorted Array

This C Program calculates ceiling & floor of X given a sorted array & a value X.

Here is source code of the C Program to calculate ceiling & floor of X given a sorted array & a value X. The C program is successfully compiled and run on a Linux system. The program output is also shown below.

  1. /*
  2.  * C Program to Find Ceiling & Floor of  X given a Sorted Array & a value X
  3.  */
  4.  #include <stdio.h>
  5.  
  6. /* Function to get index of ceiling of x in arr[low..high] */
  7. int ceilSearch(int arr[], int low, int high, int x)
  8. {
  9.      int i;
  10.  
  11.     /* If x is smaller than or equal to first element,then return the first element */
  12.     if (x <= arr[low])
  13.     return low;
  14.  
  15.    /* Otherwise, linearly search for ceil value */
  16.    for (i = low; i < high; i++)
  17.    {
  18.        if (arr[i] == x)
  19.           return i;
  20.  
  21.        /* if x lies between arr[i] and arr[i+1] including arr[i+1], then return arr[i+1] */
  22.        if (arr[i] < x && arr[i + 1] >= x)
  23.            return i + 1;
  24.    }
  25.  
  26.    /* If we reach here then x is greater than the last element of the array,  return -1 in this case */
  27.    return -1;
  28. }
  29.  
  30. int main()
  31. {
  32.     int arr[] = {1, 2, 8, 10, 10, 12, 19};
  33.     int n = sizeof(arr)/sizeof(arr[0]);
  34.     int x = 3;
  35.     int index = ceilSearch(arr, 0, n-1, x);
  36.     if (index == -1)
  37.         printf("Ceiling of %d doesn't exist in array ", x);
  38.     else
  39.         printf("ceiling of %d is %d", x, arr[index]);
  40.     getchar();
  41.     return 0;
  42. }

$ cc pgm99.c
$ a.out
ceiling of 3 is 8

Sanfoundry Global Education & Learning Series – 1000 C Programs.

advertisement

Here’s the list of Best Books in C Programming, Data-Structures and Algorithms

If you wish to look at other example programs on Arrays, go to C Programming Examples on Arrays. If you wish to look at programming examples on all topics, go to C Programming Examples.

advertisement
advertisement
Subscribe to our Newsletters (Subject-wise). Participate in the Sanfoundry Certification contest to get free Certificate of Merit. Join our social networks below and stay updated with latest contests, videos, internships and jobs!

Youtube | Telegram | LinkedIn | Instagram | Facebook | Twitter | Pinterest
Manish Bhojasia - Founder & CTO at Sanfoundry
I’m Manish - Founder and CTO at Sanfoundry. I’ve been working in tech for over 25 years, with deep focus on Linux kernel, SAN technologies, Advanced C, Full Stack and Scalable website designs.

You can connect with me on LinkedIn, watch my Youtube Masterclasses, or join my Telegram tech discussions.

If you’re in your 40s–60s and exploring new directions in your career, I also offer mentoring. Learn more here.