28 lines
744 B
Java
28 lines
744 B
Java
package Others;
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/**
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* You can read more about Euler's totient function
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* <p>
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* See https://en.wikipedia.org/wiki/Euler%27s_totient_function
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*/
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public class EulersFunction {
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// This method returns us number of x that (x < n) and gcd(x, n) == 1 in O(sqrt(n)) time complexity;
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public static int getEuler(int n) {
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int result = n;
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for (int i = 2; i * i <= n; i++) {
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if (n % i == 0) {
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while (n % i == 0) n /= i;
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result -= result / i;
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}
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}
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if (n > 1) result -= result / n;
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return result;
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}
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public static void main(String[] args) {
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for (int i = 1; i < 100; i++) {
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System.out.println(getEuler(i));
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}
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}
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}
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