[euler/prob029] fix, merge and add MAIN() to my solution

euler/prob029-gerdr.pl

@@ -1,40 +1,46 @@
 use v6;
 
-# FIXME: incorrect result for non-square input
-
 # same algorithm as polettix' solution
 
-# range of bases
-constant A = 2..100;
+sub count-unique-powers(Int \A, Int \B --> Int) {
+	# computes number of unique powers a**b with bases \a in range 2..A
+	# and exponents \b in range 2..B
 
-# range of exponents
-constant B = 2..100;
+	my %seen-bases;
+	my $seen-values = [+] gather {
 
-my %seen-bases;
-my $seen-values = [+] gather {
+		# visit bases which are powers of preceeding ones
+		for 2..sqrt(A).Int -> \root {
+			next if %seen-bases{root};
 
-	# visit bases which are powers of preceeding ones
-	for A[0] .. sqrt(A[*-1]).Int -> \root {
-		next if %seen-bases{root};
+			my %seen-exponents;
+			my @powers = root, * * root ...^ * > A;
 
-		my %seen-exponents;
-		my @powers = root, * * root ...^ * > A[*-1];
+			for @powers Z 1..* -> \base, \exp {
+				next if %seen-bases{base};
 
-		for @powers Z 1..* -> \base, \exp {
-			next if %seen-bases{base};
+				# mark powers of \base according to their exponent
+				# relative to \root
+				%seen-exponents{(2..B).map(* * exp)} = True...*;
 
-			# mark powers of \base according to their exponent
-			# relative to \root
-			%seen-exponents{B.map(* * exp)} = True...*;
+				# avoid double-counting
+				%seen-bases{base} = True;
+			}
 
-			# avoid double-counting
-			%seen-bases{base} = True;
+			take +%seen-exponents;
 		}
 
-		take +%seen-exponents;
 	}
 
+	# without duplicates, the result would be (A - 1) * (B - 1)
+	(A - 1 - %seen-bases) * (B - 1) + $seen-values
 }
 
-# without duplicates, the result would be A * B
-say (A - %seen-bases) * B + $seen-values;
+sub MAIN(Int $A = 100, Int $B = 100, Bool :$verify) {
+	say 'got ',
+		count-unique-powers $A, $B;
+
+	say 'expected ',
+		+(2..$A X=> 2..$B).classify({ .key ** .value })
+		if $verify;
+}