Earliest difference between prime gaps: Difference between revisions

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m (Python example)
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Gap 276 starts at 649,580,171, gap 278 starts at 4,260,928,601, difference is 3,611,348,430.
Gap 276 starts at 649,580,171, gap 278 starts at 4,260,928,601, difference is 3,611,348,430.
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</pre>

=={{header|Phix}}==
{{trans|Wren}}
<!--<lang Phix>(phixonline)-->
<span style="color: #008080;">with</span> <span style="color: #008080;">javascript_semantics</span>
<span style="color: #008080;">constant</span> <span style="color: #000000;">limit</span> <span style="color: #0000FF;">=</span> <span style="color: #008080;">iff</span><span style="color: #0000FF;">(</span><span style="color: #7060A8;">platform</span><span style="color: #0000FF;">()=</span><span style="color: #004600;">JS</span><span style="color: #0000FF;">?</span><span style="color: #000000;">1e7</span><span style="color: #0000FF;">:</span><span style="color: #000000;">1e8</span><span style="color: #0000FF;">),</span>
<span style="color: #000000;">gslim</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">250</span>
<span style="color: #004080;">sequence</span> <span style="color: #000000;">primes</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">get_primes_le</span><span style="color: #0000FF;">(</span><span style="color: #000000;">limit</span><span style="color: #0000FF;">*</span><span style="color: #000000;">5</span><span style="color: #0000FF;">),</span>
<span style="color: #000000;">gapstarts</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">gslim</span><span style="color: #0000FF;">)</span>
<span style="color: #008080;">for</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">2</span> <span style="color: #008080;">to</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">primes</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">do</span>
<span style="color: #004080;">integer</span> <span style="color: #000000;">gap</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">primes</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]-</span><span style="color: #000000;">primes</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">]</span>
<span style="color: #008080;">if</span> <span style="color: #000000;">gapstarts</span><span style="color: #0000FF;">[</span><span style="color: #000000;">gap</span><span style="color: #0000FF;">]=</span><span style="color: #000000;">0</span> <span style="color: #008080;">then</span>
<span style="color: #000000;">gapstarts</span><span style="color: #0000FF;">[</span><span style="color: #000000;">gap</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">primes</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">]</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
<span style="color: #004080;">integer</span> <span style="color: #000000;">pm</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">10</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">gap1</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">2</span>
<span style="color: #008080;">while</span> <span style="color: #004600;">true</span> <span style="color: #008080;">do</span>
<span style="color: #008080;">while</span> <span style="color: #000000;">gapstarts</span><span style="color: #0000FF;">[</span><span style="color: #000000;">gap1</span><span style="color: #0000FF;">]=</span><span style="color: #000000;">0</span> <span style="color: #008080;">do</span> <span style="color: #000000;">gap1</span> <span style="color: #0000FF;">+=</span> <span style="color: #000000;">2</span> <span style="color: #008080;">end</span> <span style="color: #008080;">while</span>
<span style="color: #004080;">integer</span> <span style="color: #000000;">start1</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">gapstarts</span><span style="color: #0000FF;">[</span><span style="color: #000000;">gap1</span><span style="color: #0000FF;">],</span>
<span style="color: #000000;">gap2</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">gap1</span> <span style="color: #0000FF;">+</span> <span style="color: #000000;">2</span>
<span style="color: #008080;">if</span> <span style="color: #000000;">gapstarts</span><span style="color: #0000FF;">[</span><span style="color: #000000;">gap2</span><span style="color: #0000FF;">]=</span><span style="color: #000000;">0</span> <span style="color: #008080;">then</span>
<span style="color: #000000;">gap1</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">gap2</span> <span style="color: #0000FF;">+</span> <span style="color: #000000;">2</span>
<span style="color: #008080;">else</span>
<span style="color: #004080;">integer</span> <span style="color: #000000;">start2</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">gapstarts</span><span style="color: #0000FF;">[</span><span style="color: #000000;">gap2</span><span style="color: #0000FF;">],</span>
<span style="color: #000000;">diff</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">abs</span><span style="color: #0000FF;">(</span><span style="color: #000000;">start2</span> <span style="color: #0000FF;">-</span> <span style="color: #000000;">start1</span><span style="color: #0000FF;">)</span>
<span style="color: #008080;">if</span> <span style="color: #000000;">diff</span><span style="color: #0000FF;">></span><span style="color: #000000;">pm</span> <span style="color: #008080;">then</span>
<span style="color: #7060A8;">printf</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"Earliest difference &gt;%,d between adjacent prime gap starting primes:\n"</span><span style="color: #0000FF;">,{</span><span style="color: #000000;">pm</span><span style="color: #0000FF;">})</span>
<span style="color: #7060A8;">printf</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"Gap %d starts at %,d, gap %d starts at %,d, difference is %,d.\n\n"</span><span style="color: #0000FF;">,</span>
<span style="color: #0000FF;">{</span><span style="color: #000000;">gap1</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">start1</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">gap2</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">start2</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">diff</span><span style="color: #0000FF;">})</span>
<span style="color: #008080;">if</span> <span style="color: #000000;">pm</span><span style="color: #0000FF;">=</span><span style="color: #000000;">limit</span> <span style="color: #008080;">then</span> <span style="color: #008080;">exit</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
<span style="color: #000000;">pm</span> <span style="color: #0000FF;">*=</span> <span style="color: #000000;">10</span>
<span style="color: #008080;">else</span>
<span style="color: #000000;">gap1</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">gap2</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">while</span>
<!--</lang>-->
Output same as Wren. Takes 5s on desktop/Phix but would take 17s under p2js so limited that to keep it under 2s.
A limit of 1e9 needs 64 bit (hence not p2js compatible), and a multiplier of 5, and a gslim of 354, and takes
2 mins 43s, but matched the output of Julia, which managed it in 40s. Python needed more memory than I've got
for 1e9, but took 15s for a limit of 1e8, while Wren (bless, also 1e8) took just over 3 minutes.


=={{header|Python}}==
=={{header|Python}}==
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