在字符串中找出连续最长的数字串

/**************************************************************
* 华为笔试：在字符串中找出连续最长的数字串
**************************************************************/
#include <iostream>
#include <string>
#include <algorithm>
using namespace std;

int main()
{
string in;
cin >> in;

int maxLen = 0;
string out;

for (int i = 0; i < in.size(); i++)
{
int len = 0;
string tmp;
while (i < in.size() && in[i] >= '0' && in[i] <= '9')
{
tmp += in[i];
len++;
i++;
}
if (len >= maxLen)
{
maxLen = len;
out = tmp;
}
}
cout << out << endl;
cout << maxLen << endl;
}