京东神奇数，个人觉得比较好理解的方式。没有案例，求检查
#include <iostream>
#include <vector>
#include <string>
using namespace std;
string IntToStr(int i)
{
char c[256];
_itoa_s(i, c, 256, 10);
return c;
}
bool isMagicNumber(int Num)
{
int sum = 0;
string digit = IntToStr(Num);
for (string::const_iterator i = digit.begin(); i != digit.end(); i++)
{
sum += (*i);
}
if (sum % 2 != 0) //神奇数各个位数之和必为偶数
{
return false;
}
else
{
int record = 0;
//位数相继做和差运算。
for (string::const_iterator j = digit.begin(); j != digit.end(); j++)
{
if (record > 0)
record -= (*j);
else
record += (*j);
}
if (record == 0)
return true;
else
return false;
}
}
int main()
{
int l, r;
cin >> l >> r;
int countNum = 0;
for (int i = l; i <= r; i++)
{
if (isMagicNumber(i))
countNum++;
}
cout << countNum << endl;
system("pause");
return 0;
} #华为#
