字符串分割

#include <iostream>
#include <string>

using namespace std;

int main(int argc, char *argv[])
{
    string str;
    string ans(8, '0');
    while(cin >> str)
    {
        ans = "00000000";
        while(str.size() > 8)
        {
            ans = "00000000";
            ans.replace(0, 8, string(str.begin(), str.begin() + 8));
            str.assign(str.begin() + 8, str.end());
            cout << ans << endl;
        }
        ans = "00000000";
        auto length = str.size();
        ans.replace(0, length, string(str.begin(), str.end()));
        cout << ans << endl;
        str.clear();
    }
    return 0;
}