33 lines
883 B
JavaScript
33 lines
883 B
JavaScript
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// prime.js
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// Pure ECMAScript version of low level helper
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function primeCheckECMAScript(val, limit) {
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for (var i = 2; i <= limit; i++) {
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if ((val % i) == 0) { return false; }
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}
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return true;
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}
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// Select available helper at load time
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var primeCheckHelper = (this.primeCheckNative || primeCheckECMAScript);
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// Check 'val' for primality
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function primeCheck(val) {
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if (val == 1 || val == 2) { return true; }
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var limit = Math.ceil(Math.sqrt(val));
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while (limit * limit < val) { limit += 1; }
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return primeCheckHelper(val, limit);
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}
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// Find primes below one million ending in '9999'.
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function primeTest() {
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var res = [];
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print('Have native helper: ' + (primeCheckHelper !== primeCheckECMAScript));
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for (var i = 1; i < 1000000; i++) {
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if (primeCheck(i) && (i % 10000) == 9999) { res.push(i); }
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}
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print(res.join(' '));
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}
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