?????м??
????BigInteger???????+-???????????????????????????????
????????BigInteger????int ??????????????????int????????????BigInteger??
????BigInteger??????????????:
????BigInteger.zero
????BigInteger.one
????6??Java???????
????String ???????洢?????????????charAt?????????????????????????0?????
????String a = "Hello";    // a.charAt(1) = 'e'
??????substring???????????????????
????System.out.println(a.substring(0?? 4))     // output "Hell"
????????2??????λ????????????????????????????? s.substring(a?? b) ?????? b-a???????
????????????????????? + ?????
????String a = "Hello";
????String b = "world";
????System.out.println(a + "?? " + b + "!");    // output "Hello?? world!“
?????????????charAt????????????????
????7??Java??????
???????????壺
????int[] a = new int[100];
?????????????
????Arrays.fill(a??0);
????????C?????е? memset(a??0??sizeof(a));
????8???Щ???????
???????NetbeansдJ(rèn)ava????????????????package main;??????????????仰??
???????????????? Main
???????Java????????????????????????????C/C++????ACM/ICPC?????????????Щ???????Java???д?????????????Java?????????????C/C++???????
????????????????????????????

 

import ………//????c++??include
public class Main {
public static…….//?Щ???????????
public static void main(String[] args) {
Scanner cin = new Scanner(System.in);
}
}

????Java??????c/c++??????????????????????д?ɡ?

 

/*
Java???????
??BufferedReader??StringTokenizer????Scanner
*/
import java.io.*;
import java.util.*;
public class Main {
public static void main(String[] args) throws IOException {
Reader Reader =new Reader(System.in);
double x = Reader.nextDouble();
int n = Reader.nextInt();
String str = Reader.next();
}
}
class Reader {
final BufferedReader reader;
StringTokenizer tokenizer;
public Reader(InputStream input) {
reader = new BufferedReader(new InputStreamReader(input));
tokenizer = new StringTokenizer("");
}
public String next() throws IOException {
while (!tokenizer.hasMoreTokens())
tokenizer = new StringTokenizer(reader.readLine());
return tokenizer.nextToken();
}
public int nextInt() throws IOException {
return Integer.parseInt(next());
}
public double nextDouble() throws IOException {
return Double.parseDouble(next());
}
}