How to build logic in programming: Binary Search using C

How to build logic in programming: Binary Search using C: C program for binary search: This code implements binary search in c language. It can only be used for sorted arrays, but it's fast...

Binary Search using C

C program for binary search: This code implements binary search in c language. It can only be used for sorted arrays, but it's fast as compared to linear search. If you wish to use binary search on an array which is not sorted then you must sort it using some sorting technique say merge sort and then use binary search algorithm to find the desired element in the list. If the element to be searched is found then its position is printed.

The code below assumes that the input numbers are in ascending order.

C programming code for binary search

#include <stdio.h>

#include <conio.h>

void main()

{

   int c, first, last, middle, n, search, array[100];

   clrscr();

   printf("Enter number of elements\n");

   scanf("%d",&n);

   printf("Enter %d integers\n", n);

   for (c = 0; c < n; c++)

      scanf("%d",&array[c]);

   printf("Enter value to find\n");

   scanf("%d", &search);

   first = 0;

   last = n - 1;

   middle = (first+last)/2;

   while (first <= last) {

      if (array[middle] < search)

         first = middle + 1;   

      else if (array[middle] == search) {

         printf("%d found at location %d.\n", search, middle+1);

         break;

      }

      else

         last = middle - 1;

      middle = (first + last)/2;

   }

   if (first > last)

      printf("Not found! %d is not present in the list.\n", search);

   getch();  

}

Linear Searching in C

Linear search in c programming: The following code implements linear search (Searching algorithm) which is used to find whether a given number is present in an array and if it is present then at what location it occurs. It is also known as sequential search. It is very simple and works as follows: We keep on comparing each element with the element to search until the desired element is found or list ends.

Linear search c program

#include <stdio.h>

#include <conio.h>

void main()

{

   int array[100], search, c, n;

   clrscr();

   printf("Enter the number of elements in array\n");

   scanf("%d",&n);

   printf("Enter %d integer(s)\n", n);

   for (c = 0; c < n; c++)

      scanf("%d", &array[c]);

   printf("Enter the number to search\n");

   scanf("%d", &search);

   for (c = 0; c < n; c++)

   {

      if (array[c] == search)     /* if required element found */

      {

         printf("%d is present at location %d.\n", search, c+1);

         break;

      }

   }

   if (c == n)

      printf("%d is not present in array.\n", search);

   getch() ;

}

Print Pyramid structure in C

 

    *

   ***

  *****

 *******

*********

We have shown five rows above, in the program you will be asked to enter the numbers of rows you want to print in the pyramid of stars.

C programming code

#include <stdio.h>

#include <conio.h>

void main()

{

   int row, c, n, temp;

   clrscr();

   printf("Enter the number of rows in pyramid of stars you wish to see ");

   scanf("%d",&n);

   temp = n;

   for ( row = 1 ; row <= n ; row++ )

   {

      for ( c = 1 ; c < temp ; c++ )

         printf(" ");

      temp--;

      for ( c = 1 ; c <= 2*row - 1 ; c++ )

         printf("*");

      printf("\n");

   }

   getch();

}

Print Floyd's triangle using C language

C program to print Floyd's triangle:- This program prints Floyd's triangle. Number of rows of Floyd's triangle to print is entered by the user. First four rows of Floyd's triangle are as follows :-
1
2 3
4 5 6
7 8 9 10
It's clear that in Floyd's triangle nth row contains n numbers.

C programming code

#include <stdio.h>

#include<conio.h>

void main()

{

  int n, i,  c, a = 1;

  clrscr();

  printf("Enter the number of rows of Floyd's triangle to print\n");

  scanf("%d", &n);

  for (i = 1; i <= n; i++)

  {

    for (c = 1; c <= i; c++)

    {

      printf("%d ",a);

      a++;

    }

    printf("\n");

  }

  getch();

}