djiskas algorithm in matlab

main.m
function [ path, dist ] = djisktra( graph, start_node, end_node )
%DJISKTRA finds the shortest path in a graph using Djisktra's algorithm
%   Inputs:
%       graph: a weighted adjacency matrix representing the graph
%       start_node: the node to start from
%       end_node: the node to end at
%   Outputs:
%       path: an array of node indices representing the shortest path
%       dist: the total path distance

    num_nodes = size(graph, 1);
    visited = zeros(num_nodes, 1);
    dist = Inf(num_nodes, 1);
    prev = zeros(num_nodes, 1);
    dist(start_node) = 0;

    while sum(visited) < num_nodes
        [~, current] = min(dist + 1e9 * visited);
        visited(current) = 1;

        for i = 1:num_nodes
            if graph(current, i) > 0
                alt = dist(current) + graph(current, i);
                if alt < dist(i)
                    dist(i) = alt;
                    prev(i) = current;
                end
            end
        end
    end

    % Build the path
    path = [];
    node = end_node;
    while node ~= start_node
        path = [node path]; %#ok<AGROW>
        node = prev(node);
    end
    path = [start_node path];
end
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