import java.util.Scanner; import java.math.BigInteger; // 注意类名必须为 Main, 不要有任何 package xxx 信息 public class Main { public static void main(String[] args) { Scanner in = new Scanner(System.in); BigInteger a = in.nextBigInteger(); String s = ""; //转为二进制 while(a!=BigInteger.valueOf(0)){ s+=(a.mod(BigInteger.valueOf(2))).toString(); a = a.divide(BigInteger.valueOf(2)); } BigInteger weight =BigInteger.valueOf(1); a = BigInteger.valueOf(0); for(int i =s.length()-1;i>=0;i--){ BigInteger temp = weight.multiply(BigInteger.valueOf(s.charAt(i)-'0')); a = a.add(temp); weight=weight.multiply(BigInteger.valueOf(2)); } //二进制转十进制 System.out.println(a); } }
真是jaja又vava啊