I am Trying to Develop some code to alter PS file. For which I need Some Help.

The Text Given below is a part of PS file, The text starts with U1 and ends with U1, I need to have the Minimum value of Row programitically from the text. Also, if the Value is Less than 20 than, the the lowest value whose value is greater than 20 Shall be Displayed.


Suppose the Text is
F2 B (Account Number 1010467969)13 789 w

The Row position in the above would be 789.

Since there are many such rows in the text, I need to have the Minimum/Lowest Row Value.

The Text is replicated Below.

I will be Using FILETOSTR('') for the Purpose.

Thanks

U1
%%Page: 2 2
<</Duplex true /Tumble false /ManualFeed false /MediaPosition 1>>  setpagedevice
g n
/Fn3{d I/ArialBlack F}b/F12{/I 15.0 Fn3}b
F12 B (BHARAT SANCHAR NIGAM LIMITED)301 805 y
G
1 w1 594 774 2 774 L 
g n
F2 B (Account Number    1010467969)13 789 w
G
g n
F2 B (Invoice Number    10104679690030)580 789 x
G
g n
F2 B (Invoice Date    05/09/2012)229 789 w
G
g n
/F13{/I 7.4 Fn2}b
F13 B (Page 2)496 16 w
G
 g g n
/F15{/I 7.5 Fn2}b
F15 B (of 4)532 16 w
G
G
N 36 766 534 -8 i 
F8 B (Recurring Charges)38 759 w
(Product)38 749 w
(Plan)195 749 w
(Period)352 749 w
(Qty)442 749 x
(Rate)481 749 x
(Charges)568 749 x
F9 (DISCOUNT)38 737 w
(LO-KAR-LO-BAAT-OTHER)195 737 w
(01/08/12 to 31/08/12)352 737 w
(NA)442 737 x
(NA)481 737 x
(149.00)568 737 x
F8 (Total Charges \(Rs.\))38 726 w
(149.00)568 726 x
N 36 715 534 -8 i 
B (Usage Charges)38 708 w
(Phone Calls)38 699 w
(Units)258 699 w
(Duration/Volume)321 699 w
(Gross Amt)443 699 x
(Discount)505 699 x
(Net Amt)568 699 x
F9 (Local Cellular)38 688 w
(407)258 687 w
(07:29:06)321 687 w
(407.00)443 687 x
(372.00)505 687 x
(35.000)568 687 x
(Local LL BSNL)38 676 w
(460)258 675 w
(04:36:43)321 675 w
(312.00)443 675 x
(312.00)505 675 x
(0.000)568 675 x
(Special Number Band 3)38 664 w
(2)258 663 w
(00:01:27)321 663 w
(2.00)443 663 x
(0.00)505 663 x
(2.000)568 663 x
(Special Number Band 8)38 652 w
(70)258 652 w
(00:57:47)321 652 w
(0.00)443 652 x
(0.00)505 652 x
(0.000)568 652 x
(Local Landline BSNL)38 640 w
(1)258 640 w
(00:01:20)321 640 w
(1.00)443 640 x
(1.00)505 640 x
(0.000)568 640 x
(STD Cellular)38 629 w
(2)258 628 w
(00:01:44)321 628 w
(2.00)443 628 x
(0.00)505 628 x
(2.000)568 628 x
(STD Intra Circle GT50 BSNL)38 617 w
(1)258 616 w
(00:00:11)321 616 w
(1.00)443 616 x
(1.00)505 616 x
(0.000)568 616 x
F8 (Total Charges \(Rs.\))38 604 w
(725.00)443 604 x
(686.00)505 604 x
(39.00)568 604 x
/Fn4{d I/Arial-Italic F}b/F14{/I 6.3 Fn4}b
F14 (For BB 1 Unit = 1 KB)38 595 w
N 36 586 534 -8 i 
F8 B (Discounts)38 579 w
(Discount Type)38 570 w
(Period)258 570 w
(Discounts)568 570 x
F9 (LL-FREE-CALLS-50-1)38 558 w
(01/08/12 to 31/08/12)258 558 w
(-39.00)568 558 x
(LO-KAR-LO-BAAT)38 546 w
(01/08/12 to 31/08/12)258 546 w
(0.00 - 686.00 Units@100.00%)38 534 w
(-686.00)568 534 x
F8 (Total Discounts \(Rs.\))38 523 w
(-725.00)568 523 x
g n
F2 B (Plan    FRIENDS-AND-FAMILY)13 775 w
G
g n
F2 B (Phone Number / UserName    0731-2459292)580 775 x
G
U1