wordEnds

wordEnds.java

/*
 * A solution for programming problem "wordEnds":
 * http://codingbat.com/prob/p147538
 */
public String wordEnds(String str, String word) {
  StringBuffer tmp = new StringBuffer();
  int ss=0, idx=-1;
  while((idx = str.indexOf(word, ss)) >= 0) {
    ss = idx + word.length();
    if(idx-1 >= 0) tmp.append(str.charAt(idx-1));
    if(ss < str.length()) tmp.append(str.charAt(ss));
  }
  return tmp.toString();
}

wordEndsLisaMod.java

/* 
 * this one is lisa's solution with a small change
 */
public String wordEnds(String str, String word) {
  StringBuffer out = new StringBuffer ();
  int s_l = str.length(), w_l = word.length();
  for (int i = 0; i < s_l-w_l+1; i++) {
    if (str.startsWith(word, i)) {
      if (i > 0) out.append(str.charAt(i-1));
      if (i+w_l < s_l) out.append(str.charAt(i+w_l));
    }
  }
  return out.toString();
}