Well, i know this is a simple task. But am getting some unwanted lines while printing the results. The length is based on the string below every IDnumber. The length given in the input file is ignored and hence it is calculated freshly from the string itself. Please check out. 
input file:
----------
>IDnumber1 length=350
AGCTG
>IDnumber2 length=350
AGAACGT
>IDnumber3 length=350
AGC

expected output file:
----------------------
>IDnumber1 length=5
AGCTG
>IDnumber2 length=7
AGAACGT
>IDnumber3 length=3
AGC

code:
-----
#!/usr/bin/perl
open FH,"inputfile";
while(<FH>){
     $head=();$str=();
     if($_=~m/^>/){
        ($head,$x)=split(' ',$_);
     }
     else{
        $str=$_;
        chomp($str);
        $len=length($str);
     }
     print "$head Length=$len\n";
     print "$str\n";
}

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please let me know where i am going wrong !!! P.S: i have not included use strict and warnings;

In reply to printing the length of string variables by sugar

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