实验13.cpp

编写具有如下原型的函数：int f(unsigned long x, int n, int& Lxn) 它负责将整数x的第n位（从左边数第n位

#include<iostream>

using namespace std;

#define max 16
int f(unsigned long x, int n, int& Lxn)
{
	int j=0;
	int a[max];
	do
	{
		a[j]=x%10;
		x=x/10;
	}while(a[j++]);
	if(n<j)
	{
		Lxn=a[j-1-n];
		return a[n-1];
	}
	else 
	{
		Lxn=0;
		return 0;
	}

}
int main()
{
	unsigned num;
	int n,begin,end;
	cout<<"请输入一个很大的正整数:";
	cin>>num;
	cout<<endl;
	cout<<"请输入要查询整数的第n位：";
	cin>>n;
	end=f(num,n,begin);
	cout<<"从左边数第n位为："<<begin<<endl;
	cout<<"从右边数第n位为："<<end<<endl;
	return 1;
}