42 lines
1.2 KiB
JavaScript
42 lines
1.2 KiB
JavaScript
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/**
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* Depth-first search and postorder of a tree rooted at node j
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*
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* @param {Number} j The tree node
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* @param {Number} k
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* @param {Array} w The workspace array
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* @param {Number} head The index offset within the workspace for the head array
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* @param {Number} next The index offset within the workspace for the next array
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* @param {Array} post The post ordering array
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* @param {Number} stack The index offset within the workspace for the stack array
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*
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* Reference: http://faculty.cse.tamu.edu/davis/publications.html
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*/
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export function csTdfs(j, k, w, head, next, post, stack) {
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// variables
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var top = 0; // place j on the stack
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w[stack] = j; // while (stack is not empty)
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while (top >= 0) {
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// p = top of stack
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var p = w[stack + top]; // i = youngest child of p
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var i = w[head + p];
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if (i === -1) {
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// p has no unordered children left
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top--; // node p is the kth postordered node
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post[k++] = p;
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} else {
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// remove i from children of p
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w[head + p] = w[next + i]; // increment top
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++top; // start dfs on child node i
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w[stack + top] = i;
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}
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}
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return k;
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}
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