41 lines
710 B
Brainfuck
41 lines
710 B
Brainfuck
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/* An example that finds all primes between 2 and limit. */
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define primes (limit) {
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auto num, p, root, i
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prime[1] = 2;
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prime[2] = 3;
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num = 2;
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scale = 0;
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for ( p=5; p <= limit; p += 2) {
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root = sqrt(p);
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isprime = 1;
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for ( i = 1; i < num && prime[i] <= root; i++ ) {
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if ( p % prime[i] == 0 ) {
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isprime = 0;
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break;
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}
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}
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if (isprime) {
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num += 1;
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prime [num] = p;
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}
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}
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}
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print "\ntyping 'twins (10)' will print all twin primes less than 10.\n"
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define twins (limit) {
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auto i;
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i = primes(limit+2);
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for (i=1; prime[i] > 0; i++) {
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if ((prime[i]+2) == prime[i+1]) \
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print "twins are ", prime[i], " and ", prime[i+1], "\n"
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}
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}
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