mirror of
https://gitee.com/coder-xiaomo/leetcode-problemset
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177 lines
17 KiB
JSON
177 lines
17 KiB
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"title": "Minimum Number of Vertices to Reach All Nodes",
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"A node that does not have any incoming edge can only be reached by itself.",
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"Any other node with incoming edges can be reached from some other node.",
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"We only have to count the number of nodes with zero incoming edges."
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