Extreme primes: Difference between revisions

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 {{out}}
 <pre>Similar to Ring entry.</pre>
+=={{header|Go}}==
+{{trans|Wren}}
+{{libheader|GMP(Go wrapper)}}
+{{libheader|Go-rcu}}
+Based on Wren's GMP version but about 4 times slower as our GMP wrapper doesn't expose the ''Mpz_nextprime'' function. We're therefore using our own very simple version instead which is much slower.
+<syntaxhighlight lang="go">package main
+import (
+    "fmt"
+    big "github.com/ncw/gmp"
+    "rcu"
+)
+func commatizeU64(n uint64) string {
+    s := fmt.Sprintf("%d", n)
+    if n < 0 {
+        s = s[1:]
+    }
+    le := len(s)
+    for i := le - 3; i >= 1; i -= 3 {
+        s = s[0:i] + "," + s[i:]
+    }
+    if n >= 0 {
+        return s
+    }
+    return "-" + s
+}
+func nextPrime(n *big.Int) *big.Int {
+    m := new(big.Int).Set(n)
+    z := new(big.Int)
+    zero := new(big.Int)
+    one := big.NewInt(1)
+    two := big.NewInt(2)
+    if z.Rem(m, two).Cmp(zero) == 0 {
+        m.Add(m, one)
+    } else {
+        m.Add(m, two)
+    }
+    for {
+        if m.ProbablyPrime(0) {
+            return m
+        }
+        m.Add(m, two)
+    }
+}
+func main() {
+    extremes := []int{2}
+    sum := big.NewInt(2)
+    count := 1
+    p := big.NewInt(3)
+    for {
+        sum.Add(sum, p)
+        if sum.ProbablyPrime(0) {
+            count++
+            if count <= 30 {
+                extremes = append(extremes, int(sum.Uint64()))
+            }
+            if count == 30 {
+                fmt.Println("The first 30 extreme primes are:")
+                rcu.PrintTable(extremes, 6, 7, true)
+                fmt.Println()
+            } else if count%1000 == 0 {
+                m := count / 1000
+                if m < 6 || m == 30 || m == 40 || m == 50 {
+                    scount := rcu.Commatize(count)
+                    ssum := commatizeU64(sum.Uint64())
+                    sp := commatizeU64(p.Uint64())
+                    fmt.Printf("The %6sth extreme prime is: %18s for p <= %10s\n", scount, ssum, sp)
+                    if m == 50 {
+                        return
+                    }
+                }
+            }
+        }
+        p.Set(nextPrime(p))
+    }
+}</syntaxhighlight>
+{{out}}
+<pre>
+Identical to Wren output.
+</pre>
 =={{header|J}}==