5.2 Greed (and Hill Elevation).

This method is applied in such cases where a best solution is sought in a forbiddingly number of candidates. Following this method,the profit in every separate step of a procedure is maximized,without checking the consequences this might have in the next steps and to the final result.

A large number of candidates is rejected in every step of a greedy method,which has as a result the drastic shrinking of their number.This happens because greedy methods try to get the maximum possible best in every step. Despite all that,this method is topical,it does not, take in mind the whole image,therefore it is shortsighted and doesn't always leads us to the correct result.It often produces,though, a solution which is "pretty near" to the best solution.

This first example is simply an explanation of the part that the shortsighted choice has in the result of a wrong final result.

Here we have the walls of a city,different points inside and outside of it and the time for moving between points.Those times depends on a variety of reasons.We ask for the path with the least cost to move from point A1 to the center K of the city.The greedy one would try to reach the nearer point to A1 inside the city,which is A5 with 6 time units.After that there is no way to find the less cost path.

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