蓝桥杯历届试题 小数第n位 java代码

import java.util.Scanner;
public class Main{
	public static void main(String []args) {
		Scanner scanner = new Scanner(System.in);
		long a,b,n;
		 a=scanner.nextInt();
		 b=scanner.nextInt();
		 n=scanner.nextInt();
		f(a, b, n);
	}
	private static void f(long a,long b,long n) {
		a=a%b;
		while (n-10>0) {
			a*=1e10;
			a%=b;
			n-=10;
		}
		for (int i = 0; i < n+2; i++) {
			a*=10;
			if(i>n-2) {
				System.out.print(a/b);
			}
			a%=b;
		}
	}
}