gudii9
asked on
changeXy challenge
Hi,
I am working on below challenge
http://codingbat.com/prob/p101372
Psedo code:
1. if array length is zero return 0
2. if array length is 1 and it is x return x
3. if array length is 1 and it is not x return same str
4. else find location of x and replace with y if greater than length
5. return replaced string
I wrote my code as below
I am passing all tests
How to improve/modify my design, code and any other alternate approaches. please advise
I am working on below challenge
http://codingbat.com/prob/p101372
Psedo code:
1. if array length is zero return 0
2. if array length is 1 and it is x return x
3. if array length is 1 and it is not x return same str
4. else find location of x and replace with y if greater than length
5. return replaced string
I wrote my code as below
public String changeXY(String str) {
if(str.length()==0){
return "";
}
if(str.length()==1&&"x".equals(str)){
return "y";
}
if(str.length()==1&&!"x".equals(str)){
return str;
}
if(str.length()>1){
return str.replace('x','y');
}
return null;
}
I am passing all tests
How to improve/modify my design, code and any other alternate approaches. please advise
ASKER CERTIFIED SOLUTION
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SOLUTION
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@phoffric, gudii9 has already gone through 11 recursion challenges last week. He will not learn anything by using recursion when it is not useful. He really needs to learn the API better.
I'm sorry. I was wrong. Your choice of the replace method is fine.
ASKER
any improvements or alternate approaches for this challenge?
Phoffric, told you in the first comment above here. He asked you a question about line 12 of your code.
Before advising upon improvement, we first need to see your recursive solution to the challenge.
ASKER
public String changeXY(String str) {
if (str.length() == 0){
return str;
}
else if (str.charAt(0) == 'x') {
return "y" + changeXY(str.substring(1));
}
else{
return str.charAt(0) + changeXY(str.substring(1));
}
}
above passes all tests. any improvements or alternate approaches?
ASKER
public String changeXY(String str) {
String regex="x";
String substr="y";
String str2 = str.replaceAll(regex, substr);
return str2;
}
above also passed all tests
Good work!
Here is my code.
Here is my code.
public String changeXY(String str) {
int index = str.indexOf("x");
if(index == -1)return str;
return changeXY(str.substring(0, index) + "y" + str.substring(index + 1));
}
public String changeXY(String str) {
return str.replaceAll("x", "y");
}
ASKER
i like index method approach where u are finding index of x then substring just until x and concatinating with y(replacement of x) then concatenating later part of string as it is.
also your regex approach of replaceAll is more short
also your regex approach of replaceAll is more short
You are already stating what the author has observed.
But the challenge is to learn how to use recursion.