Binary Searching in An Array

Binary search is much faster than Linear search:
• It uses the technique 'divide and conquer'
• array is divided into two half.
• now the desired element is presented in first half or second half of the element
• We search until we found the element.

binary search technique

****For using Binary Search: Array should be sorted in advance.

Binary search algorithm

• Suppose we want to search value 14 and it position.
• We have to find the middle position of array.


• The value at 5 location is 11
• As we are searching 14 so we will compare middle value to our searching value in order to decide in which half of Array we have to move.

11 is less than 14.

Mean search element is in second half that mean after 5th element.
• This indicates that searching element with between series[6] series [9] binary search • Now again we will find middle value


• Compare series[7] element to 14

14=14 where we find out our value

So the position is series[7]= 7th place.

Algorithm for Binary Searching in An Array

• 1: First=1; Last=N; POS=0; flag=False
• 2. While(first<= last and(flag=false) perform step 3 to 5.
• 3. Middle =(first+ last) div 2
• 4. If(series [Middle]=('x') then [Pos=Middle; flag=true]
• 5. If (series[Midle]<('X') then first=Middle+1;
else Last=Middle-1;
• 6.if(Flag=true) then print pos
else print ' unsuccessful search'
• 7. End

Binary search in data structure

12- Array- Binary Search-Algorithm- DataStructures


Facebook Likes