36 lines
876 B
TypeScript
36 lines
876 B
TypeScript
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export {};
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const calcSum = (numbers: number[]) => numbers.reduce((a, b) => a + b);
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// Sieve of Eratosthenes time!!!
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const sumOfPrimes = (upperBound: number) => {
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let array: boolean[] = [];
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let upperLimit = Math.sqrt(upperBound);
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let output: number[] = [];
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// Make an array from 2 to (n - 1) of truthy values
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for (var i = 0; i < upperBound; i++) {
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array.push(true);
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}
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// Remove multiples of primes starting from 2, 3, 5,...
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for (var i = 2; i <= upperLimit; i++) {
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if (array[i]) {
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for (var j = i * i; j < upperBound; j += i) {
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array[j] = false;
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}
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}
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}
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// All array[i] set to true are primes
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for (var i = 2; i < upperBound; i++) {
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if (array[i]) {
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output.push(i);
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}
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}
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return calcSum(output);
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};
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console.log(sumOfPrimes(2000000));
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