i've got another assignment and it goes like this:
Bill is trying to compactly represent sequences of capital alphabetic characters from ‘A’ to ‘Z’ by folding repeating subsequences inside them. For example, one way to represent a sequence ‘AAAAAAAAAABABABCCD’ is ‘10(A)2(BA)B2©D’. He formally defines folded sequences of characters along with the unfolding transformation for them in the following way:
o A sequence that contains a single character from ‘A’ to ‘Z’ is considered to be a folded sequence. Unfolding of this sequence produces the same sequence of a single character itself.
o If S and Q are folded sequences, then SQ is also a folded sequence. If S unfolds to S’ and Q unfolds to Q’, then SQ unfolds to S’Q’.
o If S is a folded sequence, then X(S) is also a folded sequence, where X is a decimal representation of an integer number greater than 1. If S unfolds to S’, then X(S) unfolds to S’ repeated X times.
According to this definition it is easy to unfold any given folded sequence. However, Bill is much more interested in the reverse transformation. He wants to fold the given sequence in such a way that the resulting folded sequence contains the least possible number of characters.
Input
Input file contains several test cases, one per line. Each of them contains a single line of characters from ‘A’ to ‘Z’ with at least 1 and at most 100 characters.
Output
For each input case write a different output line. This must be a single line that contains the shortest possible folded sequence that unfolds to the sequence that is given in the input file. If there are many such sequences then write any one of them.
Sample Input
AAAAAAAAAABABABCCD
NEERCYESYESYESNEERCYESYESYES
Sample Output
9(A)3(AB)CCD
2(NEERC3(YES))
here is my code:
CODE
import java.io.*;
import java.util.*;
public class MP3{
public static void main(String[] args)
throws IOException{
String fileName = "e:\\inMP3.txt";
String str="";
FileReader fr = new FileReader(fileName);
BufferedReader br = new BufferedReader(fr);
Boolean repeat = true;
StringTokenizer st;
String a, b;
int x;
System.out.println( "Output:" );
while(repeat) {
str = br.readLine();
if(str==null) {
repeat=false;
break;
}
else{
st = new StringTokenizer(str);
x = st.countTokens();
a = st.nextToken();
b = st.nextToken();
if(a.equals(b)){
for(int i=0; i<x; i++){
int count=0;
count++;
System.out.print(count+"("+a+")");
}
}
else{
break;
}
}
}
fr.close();
}
}
please check it. it throws a noSuchElement exception when i execute it. and i don't think it would count a repeating group of characters.
again, i'm sorry for my terrible code... but please, i need help.
This post has been edited by jayman9: 17 Aug, 2007 - 02:10 AM
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