《演算法（英文版·第4版）》勘誤（第621頁）

《演算法（英文版·第4版）》第 621 頁：

It builds the MST as follows:

• Adds 0 to the MST and all edges in its adjacency list to the priority queue, since each such edge is the best (only) known connection between a tree vertex and a non-tree vertex.
• Adds 7 and 0-7 to the MST and 1-7 and 5-7 to the priority queue. Edges 4-7 and 2-7 do not affect the priority queue because their weights are not less than the weights of the known connections from the MST to 4 and 2, respectively.
• Adds 1 and 1-7 to the MST and 1-3 to the priority queue.
• Adds 2 and 0-2 to the MST, replaces 0-6 with 2-6 as the shortest edge from a tree vertex to 6, and replaces 1-3 with 2-3 as the shortest edge from a tree vertex to 3.
• Adds 3 and 2-3 to the MST.
• Adds 5 and 5-7 to the MST and replaces 0-4 with 4-5 as the shortest edge from a tree vertex to 4.
• Adds 4 and 4-5 to the MST.
• Adds 6 and 6-2 to the MST.

After having added V-1 edges, the MST is complete and the priority queue is empty.

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上面的圖和文字說明都有錯誤，修改如下：

It builds the MST as follows:

• Adds 0 to the MST and all edges in its adjacency list to the priority queue, since each such edge is the best (only) known connection between a tree vertex and a non-tree vertex.
• Adds 7 and 0-7 to the MST and 1-7 and 5-7 to the priority queue. Replace 0-4 with 4-7 as the shortest edge from a tree vertex to 4, and 2-7 do not affect the priority queue because its weight is not less than the weight of 0-2.
• Adds 1 and 1-7 to the MST and 1-3 to the priority queue.
• Adds 2 and 0-2 to the MST, replaces 6-0 with 6-2 as the shortest edge from a tree vertex to 6, and replaces 1-3 with 2-3 as the shortest edge from a tree vertex to 3.
• Adds 3 and 2-3 to the MST.
• Adds 5 and 5-7 to the MST and replaces 4-7 with 4-5 as the shortest edge from a tree vertex to 4.
• Adds 4 and 4-5 to the MST.
• Adds 6 and 6-2 to the MST.

After having added V-1 edges, the MST is complete and the priority queue is empty.

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上面是使用即時 Prim 演算法來計算示例加權圖的最小生成樹的軌跡。這個示例加權圖及其最小生成樹如下所示：

它的鄰接表表示如下所示：