searching

searching

1. the simplest search method is to search at the top, and check every element until the search term is found or the entire list has been searched this is called a linear search

   • with large arrays, linear search can be slow. if there are a million values, then all of them may need checking before the result is found. the bigger the data to be searched, the longer the search will take
   • advantages - simple algorithm, works on any list
   • disadvantages - slow on large lists

2. if the data is ordered, then a binary search can be used. with a binary search, we check the middle value of the list, then depending on whether is is higher or lower than the search value, eliminate half and try again

   • a binary search is MUCH faster than a linear search. a million values can be searched in 20 steps (compared to 100000 in a linear search). ONLY works when the data is sorted (numerically or alphabetically)
   • advantages - very fast on large lists
   • disadvantages - only works if the data is sorted.