相关疑难解决方法(0)

我有一个简单的类货币与重载运算符<<.我不知道如何将数字与空格每3位数分开,所以看起来像是:"1 234 567 ISK".

#include <cstdlib>
#include <iostream>

using namespace std;

class Currency
{
    int val;
    char curr[4];

    public:
    Currency(int _val, const char * _curr)
    {
        val = _val;
        strcpy(curr, _curr);
    }

    friend ostream & operator<< (ostream & out, const Currency & c);
};

ostream & operator<< (ostream & out, const Currency & c)
{
    out << c.val<< " " << c.curr;
    return out;
}

int main(int argc, char *argv[])
{
    Currency c(2354123, "ISK");
    cout << c;
}

我感兴趣的是某种最简单的解决方案.