- finds an approximate solution for [[Traveling Sales Problem Optimization Version (TSP-OPT)]]
- given the graph $G = (V, E)$ compute its [[Minimum Spanning Trees (MST)]]
- run $DFS$ on that $MST$, record vertices visited
- i.e ABCDCECBA
- return unique vertices in pre-order as tour, skipping any repeated vertices
- ABCDE
- but first vertex must be appended at end, so real answer is **ABCDEA**
- runtime of $O(n\,log(n))$
- when $G$ satisfies the triangle inequality, this algorithm achieves an approximation factor of 2