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$ curl repovive.com/roadmaps/graph-theory/subtree-dp/subordinates-implementation

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$ curl repovive.com/roadmaps/graph-theory/subtree-dp/subordinates-implementation

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CSES 1674 Subordinates - Implementation - Subtree DP | Graph Theory | Repovive

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Graph Theory37 sections · 1633 units81h total

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CSES 1674 Subordinates - Implementation

Code with adjacency list

Here is the implementation:

size = array of size n + 1

function dfs(v, parent):
    size[v] = 1
    for u in adj[v]:
        if u != parent:
            dfs(u, v)
            size[v] = size[v] + size[u]

dfs(1, -1)

for v from 1 to n:
    print size[v] - 1

Time: $O(n)$ (visit each node once). Space: $O(n)$ for the size array and recursion stack.