FindKeywords

package com.person;

import java.util.HashMap;
import java.util.Map;

public class FindKeywords {
    public int getSubString(String s, String[] keywords) {
        Map<String, Integer> keywordMap = new HashMap<>();
        Map<String, Integer> stMap = new HashMap<>();


        for (String key: keywords) {
            keywordMap.put(key, keywordMap.getOrDefault(key, 0)+1);
        }

        String[] st = s.split("\\s+");

       int i=0, j=0;
       int minCount = Integer.MAX_VALUE;

       while (i<st.length && j<st.length) {
           if (keywordMap.containsKey(st[j])) {
               stMap.put(st[j], stMap.getOrDefault(st[j], 0) + 1);
           }
           j++;

           while (i<j && doMapsMatch(stMap, keywordMap)) {
               minCount = Math.min(minCount, j - i);

               if (stMap.containsKey(st[i])) {
                   int stCount = stMap.get(st[i]);
                   stCount -= 1;
                   if (stCount == 0) {
                       stMap.remove(st[i]);
                   } else {
                       stMap.put(st[i], stCount);
                   }
               }

               i++;
           }
       }
        return minCount;
    }

    private static boolean doMapsMatch(Map<String, Integer> mp1, Map<String, Integer> mp2) {
        if (mp1.size() != mp2.size()) {
            return false;
        }

        for (Map.Entry<String, Integer> entry: mp1.entrySet()) {
            if (!mp2.containsKey(entry.getKey()) || ( mp2.containsKey(entry.getKey()) && !mp2.get(entry.getKey()).equals(entry.getValue()))) {
                return false;
            }
        }

        return true;
    }

    public static void main(String[] args) {
        String s = "Hey green hero why apple end apple cat blow hello apple apple cat blow";
        String[] keywords = new String[]{"apple", "apple", "cat", "blow"};

        FindKeywords ob = new FindKeywords();
        int ans = ob.getSubString(s, keywords);
        System.out.println(ans);
    }
}