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$ curl repovive.com/roadmaps/graph-theory/floyd-warshall-algorithm/implementation-find-the-city

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$ curl repovive.com/roadmaps/graph-theory/floyd-warshall-algorithm/implementation-find-the-city

Repovive

LeetCode 1334 Find the City - Implementation - Floyd-Warshall Algorithm | Graph Theory | Repovive

Repovive.

Graph Theory37 sections · 1633 units81h total

Open in Course

LeetCode 1334 Find the City - Implementation

(Using Floyd-Warshall)

Initialize $dist$ with edge weights, run Floyd-Warshall. For each city $i$ , count reachable cities within threshold:

min_count := n
result := 0
for i from 0 to n - 1
    count := 0
    for j from 0 to n - 1
        if i != j and dist[i][j] <= threshold then
            count := count + 1
    if count <= min_count then
        min_count := count
        result := i
return result

Return result. The <= in the final comparison ensures ties go to the larger city.

This runs in $O(n^3)$ time and uses $O(n^2)$ space.