45 lines
1.1 KiB
Java
45 lines
1.1 KiB
Java
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package com.zerroi.leetcode.Three27;
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import java.util.ArrayList;
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import java.util.List;
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public class CountSubstrings {
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public static void main(String[] args) {
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Solution solution = new Solution();
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String s = "abc";
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int res = solution.countSubstrings(s);
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System.out.println("res = " + res);
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}
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}
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class Solution {
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private List<String> path = new ArrayList<>();
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public int countSubstrings(String s) {
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backtrack(s, 0);
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return path.size();
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}
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private void backtrack(String s, int start) {
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if (start >= s.length()) {
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return;
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}
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for (int i = start; i < s.length(); i++) {
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if (isPalindrome(s, start, i)) {
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String str = s.substring(start, i + 1);
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path.add(str);
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} else {
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continue;
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}
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backtrack(s, i + 1);
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}
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}
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private boolean isPalindrome(String s, int startIndex, int end) {
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for (int i = startIndex, j = end; i < j; i++, j--) {
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if (s.charAt(i) != s.charAt(j)) {
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return false;
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}
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}
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return true;
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}
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}
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