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/**
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 * @param {number[][]} graph
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 * @return {number}
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 */
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var shortestPathLength = function (graph) {
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  const n = graph.length;
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  const allVisited = (1 << n) - 1;
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  const queue = [];
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  const visited = new Set();
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  for (let i = 0; i < n; i++) {
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    queue.push([1 << i, i, 0]);
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    visited.add((1 << i) * 16 + i);
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  }
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  while (queue.length > 0) {
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    const [mask, node, dist] = queue.shift();
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    if (mask === allVisited) {
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      return dist;
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    }
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    for (const neighbor of graph[node]) {
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      const newMask = mask | (1 << neighbor);
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      const hashValue = newMask * 16 + neighbor;
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      if (!visited.has(hashValue)) {
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        visited.add(hashValue);
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        queue.push([newMask, neighbor, dist + 1]);
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      }
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    }
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  }
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  return -1;
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};