Linear & Binary Search

Linear & Binary Search

1. Linear

   • Simplest search method is to start from top
     • check every element until term is found, or everything searched
   • bad
     • big arrays mean search is slow
       • millions of values, and all needs to be checked before result found
         • bigger data longer search

2. Binary

   • if data is ordered, binary search used
     • check middle value of list, then depending on whether it is higher and lower than search value, eliminate half and try again
   • much faster than linear
   • million values searched in 20 steps
     • compared to 1000000 in linear
   • only works when data is sorted

3. Advantages

   • Linear
     • Simple algorithm
     • works on any list
   • Binear
     • very fast on large lists

4. Disadvantages

   • Linear
     • slow on large lists
   • Binary
     • only works if data is sorted