90 lines
2.8 KiB
Java
90 lines
2.8 KiB
Java
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/*This Java program is to Implement Suffix arrayIn computer science, a suffix array is a sorted array of all suffixes of a string. It is a simple, yet powerful data structure which is used, among others, in full text indices, data compression algorithms and within the field of bioinformatics.*/
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import java.io.BufferedReader;
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import java.io.IOException;
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import java.io.InputStreamReader;
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public class SuffixArray
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{
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private String[] text;
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private int length;
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private int[] index;
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private String[] suffix;
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public SuffixArray(String text)
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{
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this.text = new String[text.length()];
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for (int i = 0; i < text.length(); i++)
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{
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this.text[i] = text.substring(i, i+1);
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}
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this.length = text.length();
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this.index = new int[length];
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for (int i = 0; i < length; i++)
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{
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index[i] = i;
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}
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suffix = new String[length];
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}
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public void createSuffixArray()
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{
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for(int index = 0; index < length; index++)
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{
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String text = "";
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for (int text_index = index; text_index < length; text_index++)
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{
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text+=this.text[text_index];
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}
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suffix[index] = text;
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}
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int back;
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for (int iteration = 1; iteration < length; iteration++)
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{
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String key = suffix[iteration];
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int keyindex = index[iteration];
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for (back = iteration - 1; back >= 0; back--)
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{
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if (suffix[back].compareTo(key) > 0)
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{
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suffix[back + 1] = suffix[back];
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index[back + 1] = index[back];
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}
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else
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{
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break;
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}
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}
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suffix[ back + 1 ] = key;
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index[back + 1 ] = keyindex;
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}
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System.out.println("SUFFIX \t INDEX");
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for (int iterate = 0; iterate < length; iterate++)
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{
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System.out.println(suffix[iterate] + "\t" + index[iterate]);
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}
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}
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public static void main(String...arg)throws IOException
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{
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String text = "";
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BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
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System.out.println("Enter the Text String ");
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text = reader.readLine();
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SuffixArray suffixarray = new SuffixArray(text);
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suffixarray.createSuffixArray();
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}
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}
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/*
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Enter the Text String
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banana
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SUFFIX INDEX
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a 5
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ana 3
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anana 1
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banana 0
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na 4
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nana 2
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