Java Number Power power(final long x, final long n, final long p)

Description

Return x^n (mod p) Assumes x, n >= 0, p > 0, x < p, 0^0 = 1 Overflow may occur if p > 31 bits.

License

Apache License

Declaration

public static long power(final long x, final long n, final long p) 

Method Source Code

//package com.java2s;
/**/*from w w w .  ja  v a  2 s  .  c  om*/
 * Copyright (C) [2013] [The FURTHeR Project]
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *         http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

public class Main {
    /**
     * Return x^n (mod p) Assumes x, n >= 0, p > 0, x < p, 0^0 = 1 Overflow may occur if p
     * > 31 bits.
     */
    public static long power(final long x, final long n, final long p) {
        if (n == 0)
            return 1;

        long tmp = power((x * x) % p, n / 2, p);

        if (n % 2 != 0)
            tmp = (tmp * x) % p;

        return tmp;
    }
}

Related

1. pow3_strict(final float a)
2. pow4(double val)
3. pow9(final double x)
4. powDecay(double x, double y)
5. power(double d, int exp)
6. power(int base, int power)
7. power(int i)
8. power(int val, int numOfPower)
9. power(int x, int n)