### Introduction

The Steiner problem consists of finding the minimal length networks than link a finite number of given points.

One of the applications of this problem is the construction of a network of roads between given cities; if the cost is proportional to the length of the road and if there are no additional constraints, the cheapest network of roads is a minimal network.

Find the Minimal Network that links...

Other situations where considering minimal networks may be of interest are:

(*) This web page was done by Isabel Cristina Lopes in the 5th year internship of the Math course at the Science Faculty of the University of Porto.

Difficulty level: Upper Secondary, University