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    <p>I advise you to look at <a href="http://www.topcoder.com/tc?module=Static&amp;d1=tutorials&amp;d2=graphsDataStrucs3" rel="noreferrer">TopCoder</a> tutorial that have very pragmatic apporach. You will need to find out how STL priority queue works and make sure you don't have any <code>negative edge weights</code> in your graph.</p> <p>Decent full implementation can be found <a href="http://zobayer.blogspot.com/2009/12/dijkstras-algorithm-in-c.html" rel="noreferrer">here</a>. You will have to add Path vector to it and implement <code>RecoverPath</code> method in order to get nodes on path from source to sink. To use this solution you will also need to convert your <code>adjacency matrix</code> to <code>adjacency list</code> in following way:</p> <pre><code>for (int i=0;i&lt;nNodes;i++) for (int j=0;j&lt;nNodes;j++){ if (costMatrix[i][j] != NO_EDGE_VALUE){ G[i].pb(make_pair(j,costMatrix[i],[j])); } } </code></pre> <p>EDIT: If your graph is dense I would advise you to use <a href="http://en.wikipedia.org/wiki/Bellman%E2%80%93Ford_algorithm" rel="noreferrer">Ford Bellman</a> algorithm is much simpler and shouldn't be much slower.</p> <p>EDIT2: To calculate path you should add in the header</p> <pre><code>int P[MAX]; /*array with links to parents*/ for(i=0; i&lt;=nodes; i++) P[i] = -1; /*magic unset value*/ // dijkstra while(!Q.empty()) { .... if(!F[v] &amp;&amp; D[u]+w &lt; D[v]) { D[v] = D[u] + w; /*By setting P[v] value we will remember what is the previous node on path from source */ P[v] = u; // &lt;-- added line Q.push(pii(v, D[v])); } ... } </code></pre> <p>Then you have to add RecoverPath method (it works only when path exists)</p> <pre><code>vector&lt;int&gt; RecoverPath(int src, int dest){ vector&lt;int&gt; path; int v = dest; while (v != src) { path.push_back(v); v = P[v]; } path.push_back(src); std::reverse(path.begin(),path.end()); return path; } </code></pre>
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    1. CO+1, TopCoder's link is excellent.
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      1. USAlexandre C.
    2. COin the above link, which is matrix row,column,and value like matrix[row][column]=value
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    3. COin this implementation instead of costMatrix you have vector< pii > G[MAX]; where G[x] holds out edges of x node, so to get matrix[row][col] you have to search G[row] for col value and return its cost.
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