Largest palindrome product: Difference between revisions

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@@ Line 19: / Line 19: @@
 =={{header|Go}}==
 {{trans|Wren}}
-digit integers are within the range of Go's uint64 type though finding the result for 9-digit number products takes a while - around 30 seconds on my machine.
+digit integers are within the range of Go's uint64 type though finding the result for 9-digit number products takes a while - around 15 seconds on my machine.
 <lang go>package main
@@ Line 44: / Line 44: @@
             j := reverse(i)
             p := i*pow + j
-            // all palindromic numbers with an even number of digits are divisible by 11
+            // we assume here the palindromes will end in 9
-            // and we assume here will end in 9
+            if p%10 != 9 {
-            if p%11 != 0 || p%10 != 9 {
                 continue
             }
-            for k := high; k >= low+1; k-- {
+            // k can't be even nor end in 5 to produce a product ending in 9
+            for k := high; k > low; k -= 2 {
+                if k % 10 == 5 {
+                    continue
+                }
                 l := p / k
                 if l > high {