Java > String-2 > zipZap (CodingBat Solution)

Problem:

Look for patterns like "zip" and "zap" in the string -- length-3, starting with 'z' and ending with 'p'. Return a string where for all such words, the middle letter is gone, so "zipXzap" yields "zpXzp".

zipZap("zipXzap") → "zpXzp"
zipZap("zopzop") → "zpzp"
zipZap("zzzopzop") → "zzzpzp"


Solution:

public String zipZap(String str) {
  int len = str.length();
  String finalString = "";
  
  for (int i = 0; i < len; i++) {
    finalString += str.substring(i,i+1);
    if (i > 0 && i < len-1) {
      if (str.charAt(i-1) == 'z' && str.charAt(i+1) == 'p')
        finalString = finalString.substring(0,finalString.length()-1);
    }
  }
  return finalString;
}

22 comments:

  1. UnknownJuly 23, 2014 at 2:46 PM

    public String zipZap(String str) {
    String first="";
    String last="";
    String temp="";
    for(int i=0;i<str.length()-2;i++){
    temp=str.substring(i,i+3);
    if(temp.charAt(0)=='z' && temp.charAt(2)=='p'){
    first=str.substring(0,i+1);
    last=str.substring(i+2);
    str=first+last;
    }
    }
    return str;
    }

    ReplyDelete
    Replies
    1. AnonymousSeptember 17, 2014 at 3:23 PM

      public String zipZap(String str) {
      String first="";
      String last="";
      String temp="";
      String SOLVE = "";
      for(int i=0;i<str.length()-2;i++){
      temp=str.substring(i,i+3);
      if(temp.charAt(0)=='z' && temp.charAt(2)=='p'){
      first=str.substring(0,i+1);
      last=str.substring(i+2);
      SOLVE=SOLVE+first+last;
      i = i+3;
      }
      SOLVE = SOLVE+ temp;
      i = i+3;
      }
      return SOLVE;
      }

      Delete
    2. UnknownDecember 3, 2014 at 10:37 AM

      Easy solution with StringBuilder

      public String zipZap(String str) {
      StringBuilder sb = new StringBuilder(str);
      for(int i = 0; i < sb.length() - 2; i++){
      if(sb.charAt(i) == 'z' && sb.charAt(i+2) == 'p'){
      sb.deleteCharAt(i+1);
      }
      }
      String resultString = sb.toString();
      return resultString;
      }

      Delete
    3. JakeDecember 30, 2014 at 2:19 AM

      Faster :P

      public String zipZap(String str) {
      return str.replaceAll("z.p", "zp");
      }

      Delete
  2. JakeDecember 30, 2014 at 2:19 AM

    Definitely the quickest way --

    public String zipZap(String str) {
    return str.replaceAll("z.p", "zp");
    }

    ReplyDelete
  3. AustinOctober 21, 2017 at 5:24 PM

    String result = "";
    int i = 0;

    while (i < str.length())
    {
    if (i != 0 && i != str.length() - 1 && str.charAt(i - 1) == 'z' && str.charAt(i + 1) == 'p')
    {
    i++;
    }
    else
    {
    result += str.charAt(i);
    i++;
    }
    }

    return result;

    ReplyDelete
  4. JabedJanuary 30, 2018 at 10:14 PM

    public String zipZap(String str) {
    for(int i=0;i<str.length()-2;i++){
    if(str.charAt(i)=='z'&&str.charAt(i+2)=='p'){str=str.substring(0,i+1)+str.substring(i+2);}
    }
    return str;
    }

    ReplyDelete
  5. anilMarch 9, 2018 at 2:08 AM

    public String zipZap(String str) {

    String temp = "";
    int len = str.length();

    if(str.length() <= 2)
    {
    return str;
    }

    for(int i=0;i<len-2;i++)
    {
    char s1 = str.charAt(i);
    char s2 = str.charAt(i+2);

    if(s1 == 'z' && s2 == 'p')
    {
    temp = temp + str.charAt(i) + str.charAt(i+2);
    i = i+2;
    }
    else
    {
    temp = temp + str.charAt(i) ;
    }
    }

    if(str.charAt(len -3) != 'z')
    {
    temp = temp + str.charAt(len-2) + str.charAt(len-1);
    }
    return temp ;
    }

    ReplyDelete
  6. UnknownOctober 9, 2018 at 7:50 AM

    public String zipZap(String str) {
    for (int i=0; i<str.length()-2; i++){
    if(str.charAt(i) == 'z' && str.charAt(i+2) == 'p'){
    str = str.substring(0, i+1) + str.substring(i+2);
    }
    }
    return str;
    }

    ReplyDelete
  7. UnknownOctober 26, 2018 at 10:25 AM

    //Just to add something for fun

    public String zipZap(String str) {

    int[] indexArray = new int[str.length()];
    String newStr="";

    if(str.length()<3){
    return str;
    }

    for (int i = 0; i<str.length(); i++){
    indexArray[i]=0;
    }


    for (int i = 0; i<str.length()-2; i++){
    if(str.charAt(i)=='z' && str.charAt(i+2)=='p'){
    indexArray[i+1]=1;
    }
    }


    for (int i = 0; i<str.length(); i++){
    if(indexArray[i]==0){
    newStr=newStr+str.charAt(i);
    }
    }

    return newStr;
    }

    ReplyDelete
  8. beginnerAugust 11, 2019 at 10:43 AM

    for (int i=0 ; i<str.length() -2 ; i++)
    {
    if ( str.charAt(i)=='z' && str.charAt(i+2)=='p')
    str= str.substring(0,i+1)+str.substring(i+2);
    }
    return str;

    ReplyDelete
  9. Cem UndenDecember 25, 2019 at 5:42 PM

    Recursion :

    public String zipZap(String str) {

    if ( str.length() < 3 )
    // Since the length of zip , zap or any z.p is 3
    return str;

    if( str.charAt(0)=='z' && str.charAt(2)=='p' )
    return ""+str.charAt(0)+str.charAt(2)+zipZap(str.substring(3));
    return str.charAt(0)+zipZap(str.substring(1));
    }

    ReplyDelete
  10. UnknownJuly 23, 2020 at 2:52 PM

    public String zipZap(String str) {
    String change = "";
    for (int i = 0; i < str.length(); i++)
    {
    if (i + 2 < str.length() && str.charAt(i) == 'z' && str.charAt(i + 2) == 'p')
    {
    change += (str.substring(i, i+1) + str.substring(i + 2, i + 3));
    i += 2;
    }
    else
    {
    change += str.charAt(i);
    }
    }
    return change;
    }

    ReplyDelete
  11. UnknownSeptember 28, 2021 at 9:12 PM

    public String zipZap(String str) {
    int l=str.length();
    String res="";
    if ( l<3 || (!str.contains("z") || !str.contains("p")) ) return str;
    else {
    for (int i=0; i<l; i++){
    if (str.charAt(i)=='z' && str.charAt(i+2)=='p') {
    res+="z";
    res+="p";
    i+=2;
    }
    else res= res+ str.charAt(i);
    }

    }
    return res;
    }

    ReplyDelete
  12. SinuserOctober 28, 2021 at 12:28 AM

    String s = "";

    if(str.length() < 2) return str;

    if(str.length() > 2)
    {
    for(int i = 1; i < str.length() - 1; i++)
    {
    if(str.substring(i-1,i).equals("z") && str.substring(i+1,i+2).equals("p"))
    {
    continue;
    }
    else s+=str.charAt(i);
    }
    }
    return str.substring(0,1)+s+str.substring(str.length()-1);

    ReplyDelete
  13. ambanielphasApril 25, 2022 at 11:32 PM

    public String zipZap(String str) {
    String string = "";

    for(int i = 0; i < str.length(); i++){
    if ((i != 0 && i != str.length()-1) && //check i is not first or last char
    (str.charAt(i - 1) == 'z' && str.charAt(i + 1) == 'p')){
    } else {
    string += str.charAt(i);
    }
    }

    return string;
    }

    ReplyDelete
  14. Cema2009June 19, 2022 at 3:27 PM

    public String zipZap(String str) {
    return str.replaceAll("z[\\w]p", "zp");
    }

    ReplyDelete
  15. QuellaJuly 18, 2022 at 9:44 AM

    public String zipZap(String str) {
    String a="";
    if(str.length()<=2) return str;
    for(int i=0;i<str.length()-2;i++){
    if(str.charAt(i)=='z' &&str.charAt(i+2)=='p'){
    i=i+2; a=a+"zp";
    }
    else{a=a+str.charAt(i);}
    }
    if(str.charAt(str.length()-3)=='z' &&str.charAt(str.length()-1)=='p')
    return a;
    return a+ str.substring(str.length()-2);
    }

    ReplyDelete