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$ curl repovive.com/roadmaps/graph-theory/minimum-spanning-trees/road-reparation-implementation

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$ curl repovive.com/roadmaps/graph-theory/minimum-spanning-trees/road-reparation-implementation

Repovive

Road Reparation - Implementation - Minimum Spanning Trees | Graph Theory | Repovive

Repovive.

Graph Theory37 sections · 1633 units81h total

Open in Course

Road Reparation - Implementation

(Kruskal with edge count)

Here is the Kruskal implementation:

sort edges by weight
parent = array [0, 1, 2, ..., n-1]
totalCost = 0
edgeCount = 0

for (u, v, w) in edges:
    if find(u) != find(v):
        union(u, v)
        totalCost = totalCost + w
        edgeCount = edgeCount + 1

if edgeCount == n - 1:
    print totalCost
else:
    print "IMPOSSIBLE"

Time: $O(m \log m)$ for sorting. Space: $O(n)$ for Union-Find.