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Merge pull request algorithm-visualizer#200 from RudraNilBasu/master
Longest Palindromic Subsequence
2 parents b0c446c + 3a27803 commit 979dc91

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‎algorithm/category.json

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"knapsack_problem": "Knapsack Problem",
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"longest_common_subsequence": "Longest Common Subsequence",
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"longest_increasing_subsequence": "Longest Increasing Subsequence",
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"longest_palindromic_subsequence": "Longest Palindromic Subsequence",
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"max_subarray": "Maximum Subarray",
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"max_sum_path": "Maximum Sum Path",
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"pascal_triangle": "Pascal's Triangle",
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},
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"number_theory": {
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"list": {
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"euclidean_algorithm": "Euclidean Algorithm",
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"sieve_of_eratosthenes": "Sieve of Eratosthenes"
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"euclidean_algorithm": "Euclidean Algorithm",
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"sieve_of_eratosthenes": "Sieve of Eratosthenes"
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},
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"name": "Number Theory"
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},

‎algorithm/dp/longest_palindromic_subsequence/basic/code.js

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function max(a,b) {
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if(a>b){
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return a;
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} else {
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return b;
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}
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}
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logger._print("LPS for any string with length = 1 is 1");
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for(i=2;i<=N;i++) {
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logger._print("--------------------------------------------------");
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logger._print("Considering a sub-string of length "+i);
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logger._print("--------------------------------------------------");
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for(j=0;j<N-i+1;j++) {
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var k = j+i-1;
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tracer._select(j)._wait();
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tracer._notify(k)._wait();
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logger._print("Comparing "+seq[j] + " and "+seq[k]);
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if(seq[j]==seq[k] && i==2) {
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logger._print("They are equal and size of the string in the interval"+j+" to "+k+" is 2, so the Longest Palindromic Subsequence in the Given range is 2");
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matrix._notify(j,k)._wait();
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L[j][k]=2;
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matrix._setData(L);
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matrix._denotify(j,k)._wait();
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} else if(seq[j]==seq[k]) {
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logger._print("They are equal, so the Longest Palindromic Subsequence in the Given range is 2 + the Longest Increasing Subsequence between the indices "+(j+1)+" to "+(k-1));
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matrix._notify(j,k)._wait();
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matrix._select(j+1,k-1)._wait();
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L[j][k] = L[j+1][k-1] + 2;
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matrix._setData(L);
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matrix._denotify(j,k)._wait();
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matrix._deselect(j+1,k-1)._wait();
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} else {
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logger._print("They are NOT equal, so the Longest Palindromic Subsequence in the Given range is the maximum Longest Increasing Subsequence between the indices "+(j+1)+" to "+(k) + " and "+(j)+" to "+(k-1));
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matrix._notify(j,k)._wait();
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matrix._select(j+1,k)._wait();
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matrix._select(j,k-1)._wait();
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L[j][k] = max(L[j+1][k],L[j][k-1]);
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matrix._setData(L);
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matrix._denotify(j,k)._wait();
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matrix._deselect(j+1,k)._wait();
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matrix._deselect(j,k-1)._wait();
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}
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logger._print("--------------------------------------------------");
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tracer._deselect(j)._wait();
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tracer._denotify(k)._wait();
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}
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}
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logger._print("Longest Increasing Subsequence of the given string = L[0]["+(N-1)+"]="+L[0][N-1]);

‎algorithm/dp/longest_palindromic_subsequence/basic/data.js

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var tracer = new Array1DTracer('Input Text');
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var matrix = new Array2DTracer('Matrix');
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var logger = new LogTracer();
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var seq = "BBABCBCAB";
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var N;
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N = seq.length;
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var L = new Array(N);
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var i,j;
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for(i=0;i<N;i++) {
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L[i]= new Array(N);
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}
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for(i=0;i<N;i++) {
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L[i][i]=1;
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}
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tracer._setData(seq);
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matrix._setData(L);

‎algorithm/dp/longest_palindromic_subsequence/desc.json

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{
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"Longest Palindromic Subsequence": "Find the length of the longest palindromic subsequence in a given sequence",
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"Complexity": {
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"time": "O(n<sup>2</sup>)",
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"space": "O(n<sup>2</sup>)"
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},
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"References": [
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"<a href='http://www.geeksforgeeks.org/dynamic-programming-set-12-longest-palindromic-subsequence/'>GeeksForGeeks</a>"
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],
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"files": {
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"basic": "Longest Palindromic Subsequence"
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}
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}

‎gulpfile.babel.js

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'use strict';
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import path from "path";

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