Values of elements using regular expression

[Dimitri]

Hello. Please help! do not get.

File in.properties (pairs key=value) contains some sequence of lines.
Let the element with key indexi has the value j (i=1..n, j=1..m – natural numbers without leading zeros). It determines the index of an element with name valueij (j = indexi) you should work with.
1) Print the sum of values of elements, having the key valueij (see examples below).
2) Print the number of index elements with “errors” (i, j – unnatural numbers; no correct value-element for sum).

The example of the file in.properties:
index1 = 3
value11=qw
value12=4
value13 = 5.1
value14=2.7
index2=15
value21=
value22=
value23=
value24=k
value25=5
index3=1
value31= 3.14
value32=fgh
value33=5
index4=0
value41=
value42=e1
value43=2
value44=3
index5=b
value51=d
value52=e

Output:
sum = 8.24
error-lines = 3


I read from a file as follows:

ResourceBundle rb = ResourceBundle.getBundle("in");
Enumeration<String> keys = rb.getKeys();
String key;
while(keys.hasMoreElements()) {
 key = keys.nextElement();
 ...
}

How now?
I cant do the third day. Please, help!

P.S. Sorry for my english

[Dimitri]

Please help.