又一道大数。。。
import java.util.Scanner;
import java.math.BigInteger;
import java.math.BigDecimal;
public class Main
{
public static void main(String[] args)
{
Scanner scanner = new Scanner(System.in);
BigInteger f[] = new BigInteger[10005];
f[1] = BigInteger.valueOf(1);
f[2] = f[3] = f[4] = f[1];
for(int i = 5; i <= 10000; i++) {
f[i] = BigInteger.ZERO;
f[i] = f[i].add(f[i-1]);
f[i] = f[i].add(f[i-2]);
f[i] = f[i].add(f[i-3]);
f[i] = f[i].add(f[i-4]);
}
while(scanner.hasNext()) {
int n = scanner.nextInt();
System.out.println(f[n]);
}
}
}