Java Utililty Methods gcd

List of utility methods to do gcd

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Description

The list of methods to do gcd are organized into topic(s).

Method

intgcd(int a, int b)
This method finds the greatest common divisor: The largest integer or the polynomial (monomial) of highest degree that is an exact divisor or each of two or more integers or polynomials. 
int t;
while (b != 0) {
    t = b;
    b = a % b;
    a = t;
return a;
intgcd(int a, int b)
Greatest common divisor.
http://en.wikipedia.org/wiki/Greatest_common_divisor
gcd( 6, 9 ) = 3
gcd( 4, 9 ) = 1
gcd( 0, 9 ) = 9 - see: http://math.stackexchange.com/questions/27719/what-is-gcd0-a-where-a-is-a-positive-integer
gcd( 0, 0 ) = 0 - this is the only situation when the result is zero.
gcd( 0, Integer.MIN_VALUE ) = Integer.MIN_VALUE
gcd( Integer.MIN_VALUE, 0 ) = Integer.MIN_VALUE
gcd( Integer.MIN_VALUE, Integer.MIN_VALUE ) = Integer.MIN_VALUE - these are the only situations when the result is negative, because abs( Integer.MIN_VALUE ) cannot fit in int.
gcd( a, b ) = gcd( -a, b ) = gcd( a, -b ) = gcd( -a, -b ) = gcd( b, a )
The result is always positive except four exceptional situations described above. 
if (a == 0)
    return b < 0 ? -b : b;
if (b == 0)
    return a < 0 ? -a : a;
if (a < 0) {
    if (a == Integer.MIN_VALUE)
        return b & -b;
    a = -a;
...
intgcd(int a, int b)
gcd 
if (b != 0)
    return gcd(b, a % b);
else
    return a;
intgcd(int a, int b)
Find the greatest common divisor of two integers. 
if (b == 0) {
    return a;
} else {
    return gcd(b, a % b);
intgcd(int a, int b)
gcd 
while (b > 0) {
    int tmp = b;
    b = a % b;
    a = tmp;
return a;
intgcd(int a, int b)
gcd 
if (a < 0)
    a = -a;
if (b < 0)
    b = -b;
int temp;
while (b != 0) { 
    temp = b;
    b = a % b;
...
intgcd(int a, int b, int... rest)
gcd 
if (rest.length > 0) {
    int[] rest1 = new int[rest.length - 1];
    System.arraycopy(rest, 1, rest1, 0, rest1.length);
    return gcd(gcd(a, b), rest[0], rest1);
return b == 0 ? a : gcd(b, a % b);
intgcd(int firstNumber, int secondNumber)
gcd 
while (firstNumber % secondNumber != 0) {
    int temp = secondNumber;
    secondNumber = firstNumber % secondNumber;
    firstNumber = temp;
return secondNumber;
intgcd(int k, int m)
gcd 
int larger = k;
int smaller = m;
if (m > k) {
    smaller = k;
    larger = m;
while (true) {
    larger -= smaller;
...
intgcd(int largerNumber, int smallerNumber)
gcd 
return (smallerNumber == 0) ? largerNumber : gcd(smallerNumber, largerNumber % smallerNumber);