53 lines
1.0 KiB
Java
53 lines
1.0 KiB
Java
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import java.util.*;
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public class LyndonDecomposition {
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public static String minCyclicShift(String a) {
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char[] s = (a + a).toCharArray();
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int n = s.length;
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int res = 0;
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for (int i = 0; i < n / 2; ) {
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res = i;
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int j = i + 1, k = i;
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while (j < n && s[k] <= s[j]) {
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if (s[k] < s[j])
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k = i;
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else
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++k;
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++j;
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}
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while (i <= k) i += j - k;
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}
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return new String(s, res, n / 2);
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}
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public static String[] decompose(String s) {
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List<String> res = new ArrayList<>();
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char[] a = s.toCharArray();
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int n = a.length;
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int i = 0;
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while (i < n) {
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int j = i + 1, k = i;
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while (j < n && a[k] <= a[j]) {
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if (a[k] < a[j])
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k = i;
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else
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++k;
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++j;
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}
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while (i <= k) {
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res.add(s.substring(i, i + j - k));
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i += j - k;
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}
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}
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return res.toArray(new String[0]);
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}
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public static void main(String[] args) {
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String s = "bara";
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String[] decompose = decompose(s);
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System.out.println(Arrays.toString(decompose));
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System.out.println(minCyclicShift(s));
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}
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}
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