Graph

Auto-generated from src/stdlib/graph.mcrs — do not edit manually.

API

• graph_is_valid_node
• graph_new
• graph_add_edge
• graph_add_undirected
• graph_node_count
• graph_edge_count
• graph_bfs
• graph_dfs
• graph_has_path
• graph_shortest_path

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graph_is_valid_node v1.0.0

Check whether a node index is valid for this graph.

fn graph_is_valid_node(g: int[], node: int): int

Parameters

Parameter	Description
g	Graph array (from graph_new)
node	Node index to validate

Returns: 1 if node is in [0, node_count), 0 otherwise

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graph_new v1.0.0

Create a new empty graph with n nodes and capacity for 256 directed edges.

fn graph_new(n: int): int[]

Parameters

Parameter	Description
n	Number of nodes (clamped to [0, 64])

Returns: Initialized graph int[] with g[0]=0 (edges), g[1]=n (nodes)

Example

let g: int[] = graph_new(5)  // graph with 5 nodes, no edges

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graph_add_edge v1.0.0

Add a directed weighted edge to the graph.

fn graph_add_edge(g: int[], src: int, dst: int, weight: int): int[]

Parameters

Parameter	Description
g	Graph array
src	Source node index
dst	Destination node index
weight	Edge weight (use 1 for unweighted graphs)

Returns: Updated graph array; silently ignores invalid nodes or full edge list

Example

g = graph_add_edge(g, 0, 1, 5)  // edge from 0 to 1 with weight 5

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graph_add_undirected v1.0.0

Add an undirected weighted edge (adds both a→b and b→a directed edges).

fn graph_add_undirected(g: int[], a: int, b: int, weight: int): int[]

Parameters

Parameter	Description
g	Graph array
a	First node index
b	Second node index
weight	Edge weight

Returns: Updated graph array with two directed edges added

Example

g = graph_add_undirected(g, 2, 3, 2)  // bidirectional edge between 2 and 3

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graph_node_count v1.0.0

Return the number of nodes in the graph.

fn graph_node_count(g: int[]): int

Parameters

Parameter	Description
g	Graph array

Returns: Node count (g[1])

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graph_edge_count v1.0.0

Return the number of directed edges in the graph.

fn graph_edge_count(g: int[]): int

Parameters

Parameter	Description
g	Graph array

Returns: Edge count (g[0])

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graph_bfs v1.0.0

Breadth-first search from a start node, returning visit order.

fn graph_bfs(g: int[], start: int, out_visited: int[]): int[]

Parameters

Parameter	Description
g	Graph array
start	Starting node index
out_visited	int[] of length >= node_count; cells set to 1 for visited nodes

Returns: int[] of node indices in BFS visit order; empty if start is invalid

Example

let vis: int[] = [0, 0, 0, 0, 0]
let order: int[] = graph_bfs(g, 0, vis)

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graph_dfs v1.0.0

Depth-first search from a start node, returning visit order.

fn graph_dfs(g: int[], start: int, out_visited: int[]): int[]

Parameters

Parameter	Description
g	Graph array
start	Starting node index
out_visited	int[] of length >= node_count; cells set to 1 for visited nodes

Returns: int[] of node indices in DFS visit order (iterative, stack-based)

Example

let vis: int[] = [0, 0, 0, 0, 0]
let order: int[] = graph_dfs(g, 0, vis)

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graph_has_path v1.0.0

Check whether a path exists between two nodes using BFS.

fn graph_has_path(g: int[], src: int, dst: int): int

Parameters

Parameter	Description
g	Graph array
src	Source node index
dst	Destination node index

Returns: 1 if a directed path from src to dst exists, 0 otherwise

Example

let reachable: int = graph_has_path(g, 0, 3)

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graph_shortest_path v1.0.0

Find the shortest weighted path from src to all nodes using Dijkstra's algorithm.

fn graph_shortest_path(g: int[], src: int, dst: int, out_dist: int[]): int

Parameters

Parameter	Description
g	Graph array
src	Source node index
dst	Destination node index (for return value)
out_dist	int[] of length >= node_count; filled with shortest distances (-1 if unreachable)

Returns: Shortest distance from src to dst, or -1 if unreachable

Example

let dist: int[] = [0, 0, 0, 0, 0]
let d: int = graph_shortest_path(g, 0, 3, dist)

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