How does a diff algorithm work, e. g. in VCDIFF and DiffMerge? An O(ND) Difference Algorithm and its Variations (1986, Eugene W Myers) is a fantastic paper and you may want to start there It includes pseudo-code and a nice visualization of the graph traversals involved in doing the diff Section 4 of the paper introduces some refinements to the algorithm that make it very effective
algorithm - Finding all possible combinations of numbers to reach a . . . Here is a Java version which is well suited for small N and very large target sum, when complexity O(t*N) (the dynamic solution) is greater than the exponential algorithm My version uses a meet in the middle attack, along with a little bit shifting in order to reduce the complexity from the classic naive O(n*2^n) to O(2^(n 2))
algorithm - Calculate distance between two latitude-longitude points . . . Some of the answers do refer to Vincenty's formula for ellipsoids, but that algorithm was designed for use on 1960s' era desk calculators and it has stability accuracy issues; we have better hardware and software now Please see GeographicLib for a high quality library with implementations in various languages –
The best shortest path algorithm - Stack Overflow The algorithm has the same worst case complexity as Djikstra's, but in the average case the expected runtime is linear in the size of the graph, which is much faster than the pure Dijkstra The idea of the algorithm is based on the idea, that there is no need to always poll the minimum edge from the queue
algorithm - What does O (log n) mean exactly? - Stack Overflow Algorithm 1: Algorithm 1 prints hello once and it doesn't depend on n, so it will always run in constant time, so it is O(1) print "hello"; Algorithm 2: Algorithm 2 prints hello 3 times, however it does not depend on an input size Even as n grows, this algorithm will always only print hello 3 times
algorithm - How does one make a Zip bomb? - Stack Overflow The construction uses only the most common compression algorithm, DEFLATE, and is compatible with most zip parsers " "Compression bombs that use the zip format must cope with the fact that DEFLATE, the compression algorithm most commonly supported by zip parsers, cannot achieve a compression ratio greater than 1032
Big O, how do you calculate approximate it? - Stack Overflow Big-O does not measure efficiency; it measures how well an algorithm scales with size (it could apply to other things than size too but that's what we likely are interested here) - and that only asymptotically, so if you are out of luck an algorithm with a "smaller" big-O may be slower (if the Big-O applies to cycles) than a different one until you reach extremely large numbers
Newest algorithm Questions - Stack Overflow In Dijkstra’s algorithm, how do you prove that at any moment: distance[v] ≥ length(P) for shortest s → v path P where all vertices (except possibly v) are already processed (i e , not in the priority
algorithm - Peak signal detection in realtime timeseries data - Stack . . . Robust peak detection algorithm (using z-scores) I came up with an algorithm that works very well for these types of datasets It is based on the principle of dispersion: if a new datapoint is a given x number of standard deviations away from a moving mean, the algorithm gives a signal