题目

 

 和数书页有点类似，就直接数吧

#include<iostream>
using namespace std;
class q1
{
	public:
		size_t func(size_t num);
};
size_t q1::func(size_t num)
{
	size_t count = 0, tmp;
	while(num)
	{	
		tmp = num;
		while(tmp)
		{
			if(tmp%10 == 1)
				++count;
			tmp = tmp/10;
		}
		--num;
	}
	return count;
}

int main()
{
	q1 an;
	size_t num = 0;
	while(1)
	{
	cout<<"please input positive integer: ";
	cin>>num;
	cout<<num<<" to 0 include "<<an.func(num)<<" number 1 ."<<endl;
	}
	//num = 0xffffffff;
	//cout<<num<<" to 0 include "<<an.func(num)<<" number 1 ."<<endl;
}

 可循环输入，运行效果

 

 问题2