package pramp;

import java.util.HashMap;

import java.util.Map;

/**

* Split the words in a given string and print all of them in the descending

* order of their occurences count.

*

* @author: shivam.maharshi

*/

class Interview5 {

// 1. Parse the doc and figure out words split by space, punctuations or both.

// 2. Store them in a HasHMap and keep occurrences count.

// 3. Traverse HashMap keyset and sort it.

// 4. Time: O(nLog(n)): where n are the words. Space: O(n)

public static void getCount(String s) {

if (s == null || s.length() == 0)

return;

// This returns only words as array from s.

// String[] words = s.split("\\W+");

Map<String, Integer> m = new HashMap<>();

s = s.toLowerCase();

StringBuilder sb = new StringBuilder();

int i = 0;

while (i < s.length()) {

char c = s.charAt(i);

if (isWordChar(c))

sb.append(c);

else if (sb.length() == 0)

addWord(m, sb);

i++;

}

if (sb.length() == 0)

addWord(m, sb);

System.out.println(m.toString());

}

public static boolean isWordChar(char c) {

return (c <= '9' && c >= '0') || (c <= 'z' && c >= 'a');

}

public static void addWord(Map<String, Integer> m, StringBuilder sb) {

String word = sb.toString();

if (m.containsKey(word))

m.put(word, m.get(word) + 1);

else

m.put(word, 1);

sb = new StringBuilder();

}

}