o 2g @sRdZddlmZddlmZmZmZmZedZdd d Z dddZ dddZ dS)z&Helpers for manipulations with graphs.) annotations) AbstractSetIterableIteratorTypeVarTverticesAbstractSet[T]edgesdict[T, list[T]]returnIterator[set[T]]c#sPtgigdfdd |D] }|vr%|EdHqdS) aCompute Strongly Connected Components of a directed graph. Args: vertices: the labels for the vertices edges: for each vertex, gives the target vertices of its outgoing edges Returns: An iterator yielding strongly connected components, each represented as a set of vertices. Each input vertex will occur exactly once; vertices not part of a SCC are returned as singleton sets. From https://code.activestate.com/recipes/578507/. vrr r c3st|<|||D]&}|vr%|EdHq|vr=|dkr=|dks1qd|kret|d}|d=||VdSdS)N)lenappendpopsetupdate)rwscc boundariesdfsr identifiedindexstackH/home/garg/my-data/venv/lib/python3.10/site-packages/mypy/graph_utils.pyr s&     z*strongly_connected_components..dfsN)rrr r )r)rr rrrrstrongly_connected_components srsccs list[set[T]])dict[AbstractSet[T], set[AbstractSet[T]]]csXdd|Di}|D]}t}|D]}|fdd||Dq||t|<q |S)zLUse original edges to organize SCCs in a graph by dependencies between them.cSs i|] }|D]}|t|qqSr) frozenset).0rrrrr <s z prepare_sccs..c3s|]}|VqdS)Nr)r$xsccsmaprr Aszprepare_sccs..)rrr#)r r datardepsrrr'r prepare_sccs8sr,r*dict[T, set[T]]Iterable[set[T]]c#s|D] \}}||qtj|t|D]}t||<q dd|Ds1nVfdd|D}q%|rIJd|dS)aTopological sort. Args: data: A map from vertices to all vertices that it has an edge connecting it to. NOTE: This data structure is modified in place -- for normalization purposes, self-dependencies are removed and entries representing orphans are added. Returns: An iterator yielding sets of vertices that have an equivalent ordering. Example: Suppose the input has the following structure: {A: {B, C}, B: {D}, C: {D}} This is normalized to: {A: {B, C}, B: {D}, C: {D}, D: {}} The algorithm will yield the following values: {D} {B, C} {A} From https://code.activestate.com/recipes/577413/. TcSsh|]\}}|s|qSrrr$itemdeprrr ksztopsort..cs"i|] \}}|vr||qSrrr/readyrrr%os"ztopsort..z#A cyclic dependency exists amongst N)itemsdiscardrunionvalueskeys)r*krr0rr3rtopsortFs  r;N)rr r r r r )r r!r r r r")r*r-r r.) __doc__ __future__rtypingrrrrrrr,r;rrrrs   .