Method without using temporary variables: 
my $x = 3;
my $chr = 'e';
my $newchr = '1';
my $str = "Terence and Philip are sweet!\n";

print $str;

$x--;
1 while ($str =~ s/(([^$chr]*$chr){$x}([^$chr]*))$chr/$1$newchr/g);

print $str;

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In reply to Re: Replacing a given character starting with the xth occurence in a string by sachmet
in thread Replacing a given character starting with the xth occurence in a string by Anonymous Monk

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