19 lines
407 B
Java
19 lines
407 B
Java
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// https://en.wikipedia.org/wiki/Exponentiation_by_squaring
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public class BinaryExponentiation {
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public static int pow(int x, int n, int mod) {
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int res = 1;
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for (long p = x; n > 0; n >>= 1, p = (p * p) % mod) {
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if ((n & 1) != 0) {
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res = (int) (res * p % mod);
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}
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}
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return res;
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}
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// usage example
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public static void main(String[] args) {
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System.out.println(8 == pow(2, 3, 100));
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}
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}
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