binary-search

I have the following class: struct EdgeExtended { int neighborNodeId; int weight; int arrayPointer; bool isCrossEdge; }; I want to have a vector of such objects, sort it by neighborNodeId. Then I want to search for a particular neighborNodeId and return a reference to the found object inside the vector by binary search. Previously I used a map for that, so it was something like that: map<int, EdgeExtended> neighbours; ..... auto it = neighbours.find(dnodeId); if (it != neighbours.end()) { edgeMap = it->second; } Instead of map<int, EdgeExtended> neighbours; I want to have vector<EdgeExtended>

I want to do a binary search in python: def binarySearch(data, val): Where data is a sorted array and value is the value being searched for. If the value is found, I want to return the index (such that data[index] = val ). If the value is not found, I want to return the index of the item that is closest to that value. Here is what I've got: def binarySearch(data, val): high = len(data)-1 low = 0 while True: index = (high + low) / 2 if data[index] == val: return index if data[index] < val: low = index if data[index] > val: high = index Something like this should work. It returns an array with

I am watching the Berkley Uni online lecture and stuck on the below. Problem : Assume you have a collection of CD that is already sorted. You want to find the list of CD with whose title starts with "Best Of." Solution : We will use binary search to find the first case of "Best Of" and then we print until the tile is no longer "Best Of" Additional question : Find the complexity of this Algorithm. Upper Bound : Binary Search Upper Bound is O(log n), so once we have found it then we print let say k title. so it is O(logn + k) Lower Bound : Binary Search lower Bound is Omega(1) assuming we are

Easy problem and known algorithm: I have a big array with 100 members. First X members are 0, and the rest are 1. Find X. I am solving it by a binary search: Check member 50, if it is 0 - check member 75, etc, until I find adjacent 0 and 1. I am looking for an optimized algorithm for the same problem in 2-dimensions: I have 2-dimensional array 100*100. Those members that are on rows 0-X AND on columns 0-Y are 0, and the rest are 1. How to find Y and X? Simple solution: go first in X-direction and then in Y-direction. Check (0,50); If it is 0, check (0,75); until You find adjacent 0 and 1. Then