Minimum Degree of a Connected Trio in a Graph LeetCode solution in JavaScript

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var minTrioDegree = function (n, edges) {
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  // create an adjacency list of all the edges;
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  const adjacencyList = new Array(n + 1).fill(0).map(() => new Set());
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  for (const [x, y] of edges) {
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    adjacencyList[x].add(y);
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    adjacencyList[y].add(x);
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  }
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  let minimumDegree = Infinity;
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  // Find all the combinations of 3 vertices that connect
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  // and if they connect calculate the degree
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  for (let i = 1; i <= n; i++) {
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    for (let j = i + 1; j <= n; j++) {
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      for (let k = j + 1; k <= n; k++) {
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        if (
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          adjacencyList[i].has(j) &&
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          adjacencyList[i].has(k) &&
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          adjacencyList[j].has(k)
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        ) {
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          // We minus 6 because we have 3 vertices and each vertices has 2 edges
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          // going out to the 3 connecting nodes
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          const degree =
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            adjacencyList[i].size +
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            adjacencyList[j].size +
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            adjacencyList[k].size -
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            6;
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          minimumDegree = Math.min(minimumDegree, degree);
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        }
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      }
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    }
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  }
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  return minimumDegree === Infinity ? -1 : minimumDegree;
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};