binary-search

I don't know whether the term "Lazy" Binary Search is valid, but I was going through some old materials and I just wanted to know if anyone can explain the algorithm of a Lazy Binary Search and compare it to a non-lazy Binary Search. Let's say, we have this array of numbers: 2, 11, 13, 21, 44, 50, 69, 88 How to look for the number 11 using a Lazy Binary Search? As far as I am aware "Lazy binary search" is just another name for " Binary search ". Justin was wrong. The common binarySearch algorithm first checks whether the target is equal to current middle entry before proceeding to the left or

If I have the following vector {10 10 10 20 20 20 30 30} and I want a function to return the position of the integer that = X or directly the smaller element after X , like for example if I am searching for 11 I want the function to return 2 since the 2nd element(10) is the first smaller element than 11 in the vector. I tried using lower_bound but that doesn't work. int myints[] = {10,20,30,30,20,10,10,20}; vector<int> v(myints,myints+8); // 10 20 30 30 20 10 10 20 vector<int>::iterator low,up; sort (v.begin(), v.end()); // 10 10 10 20 20 20 30 30 low=lower_bound (v.begin(), v.end(), 11); //

How do I make a BST when I have an array list of 100 elements like {3,2,6,7,...,99} ? I believe TreeSet is an implementation of a binary search tree. Since integers have a natural ordering you could simply loop through your array of integers and add them all to a TreeSet<Integer> . Note also, that there is a method Arrays.binarySearch that does a binary search in a sorted array. int[] someInts = {3,2,6,7, /*...,*/ 99}; // use a TreeSet TreeSet<Integer> ints = new TreeSet<Integer>(); for (int i : someInts) ints.add(i); System.out.println(ints.contains(2)); // true System.out.println(ints

I have some data that is stored in a sorted vector. This vector is sorted by some key. I know the STL has an algorithm for checking if an element is in this sorted list. This means I can write something like this: struct MyData { int key; OtherData data; }; struct MyComparator { bool operator()( const MyData & d1, const MyData & d2 ) const { return d1.key < d2.key; } }; bool isKeyInVector( int key, const std::vector<MyData> &v ) { MyData thingToSearchFor; thingToSearchFor.key = key; return std::binary_search( v.begin(), v.end(), thingToSearchFor, MyComparator() ); } However I find the