ACM 高精度 JAVA大數 總結

定義與讀入：( cin.nextBigInteger(); )

Scanner cin = new Scanner(System.in);
BigInteger a = cin.nextBigInteger();

賦值與初始化：( BigInteger.valueOf(1); )

BigInteger x = BigInteger.valueOf(1);

四則運算（add（加）、subtract（減）、multiply（乘）、divide（除））

BigInteger a = BigInteger.valueOf(8);
BigInteger b = BigInteger.valueOf(4);
BigInteger c = BigInteger.valueOf(3);
BigInteger x = a.add(b);//x = 12
BigInteger y = a.subtract(b);//y = 4
BigInteger z = a.multiply(b);//z = 32
BigInteger r = a.divide(b);// r = 2

取餘：( a.remainder(c); )

BigInteger a = BigInteger.valueOf(8);
BigInteger c = BigInteger.valueOf(3);
BigInteger x = a.remainder(c);//x = 2

比較：( a.compareTo(b); )

//a > b return 1  
//a == b return 0 
//a < b return -1
BigInteger a = BigInteger.valueOf(2);
BigInteger b = BigInteger.valueOf(4);
BigInteger c = BigInteger.valueOf(8);
BigInteger d = BigInteger.valueOf(4);
int x = a.compareTo(b);//x == -1
int y = d.compareTo(b);//y == 0
int z = c.compareTo(b);//z == 1

 

最大公約數：( a.gcd(c); )

BigInteger a = BigInteger.valueOf(8);
BigInteger c = BigInteger.valueOf(4);
BigInteger x = a.gcd(c);//x = 4

次方：(  a.pow(2); )

BigInteger a = BigInteger.valueOf(8);
BigInteger x = a.pow(2);//x = 64