Ormiston triples: Difference between revisions
Added FreeBASIC
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</pre>
=={{header|EasyLang}}==
<syntaxhighlight>
fastfunc isprim num .
if num mod 3 = 0
return 0
.
i = 5
while i <= sqrt num
if num mod i = 0
return 0
.
i += 2
if num mod i = 0
return 0
.
i += 4
.
return 1
.
func nextprim n .
repeat
n += 2
until isprim n = 1
.
return n
.
func digs n .
while n > 0
r += pow 10 (n mod 10)
n = n div 10
.
return r
.
print "Smallest member of the first 25 Ormiston triples:"
b = 2
a = 3
repeat
c = b
dc = db
b = a
db = da
a = nextprim a
until a > 1000000000
da = digs a
if da = db and da = dc
cnt += 1
if cnt <= 25
write c & " "
.
.
.
print "Ormiston triples before 1 billion: " & cnt
</syntaxhighlight>
=={{header|F_Sharp|F#}}==
Line 860 ⟶ 914:
<1 billion: 368
</pre>
=={{header|FreeBASIC}}==
{{trans|XPLo}}
<syntaxhighlight lang="vbnet">Function GetSig(Byval N As Uinteger) As Uinteger 'Return signature of N
'A "signature" is the count of each digit in N packed into a 32-bit word
Dim As Uinteger Sig = 0
Do While N > 0
Sig += 1 Shl (N Mod 10)
N \= 10
Loop
Return Sig
End Function
Dim As Uinteger limite = 1e9
Dim Shared As Boolean Sieve(limite)
Sub MakeSieve(Size As Uinteger) 'Make prime number sieve
Dim As Uinteger Prime, i, K
Size \= 2 'ignore even numbers
For i = 0 To Size 'set Sieve flags all true
Sieve(i) = True
Next
For i = 0 To Size
If Sieve(i) Then 'found a prime, which is equal to
Prime = i * 2 + 3 ' twice the index + 3
K = i + Prime 'first multiple to strike off
While K <= Size 'strike off all multiples
Sieve(K) = False
K += Prime
Wend
End If
Next
End Sub
MakeSieve(limite)
Print "Smallest members of first 25 Ormiston triples:"
Dim As Uinteger Cnt = 0, N0 = 0, N1 = 0, Sig0 = 0, Sig1 = 0, N = 3, Sig
Dim As Double t0 = Timer
Do
If Sieve(N \ 2 - 1) Then ' is prime
Sig = GetSig(N)
If Sig = Sig0 Andalso Sig = Sig1 Then
Cnt += 1
If Cnt <= 25 Then
Print Using "#,###,###,###"; N0;
If Cnt Mod 5 = 0 Then Print
End If
End If
Sig0 = Sig1: Sig1 = Sig
N0 = N1: N1 = N
End If
If N >= limite Then Print Cnt; " Ormiston triples before one billion." : Exit Do
N += 2
Loop
Sleep</syntaxhighlight>
=={{header|Go}}==
{{trans|Wren}}
Line 2,150 ⟶ 2,261:
Limiting the search to a billion, takes about 73 seconds (68 seconds using our 'standard' sieve).
<syntaxhighlight lang="
import "./fmt" for Fmt
Line 2,210 ⟶ 2,321:
It's also far quicker - 4.4 seconds to search up to 1 billion and 43.4 seconds to search up to 10 billion.
<syntaxhighlight lang="
import "./math" for Int
import "./fmt" for Fmt
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