c++, characters combination problem

If there is a string, n characters
e.g. input string = "abcde"

How can I show all the their combinations ?
e.g. abcde, abced, abecd.... etc.

newstr = new string[instr.length()*instr.length()];
for (i = 0; i < ???; i++)
for (j = ?? ?????)

thanks!!

I hear there is a permutation function in the STL. Alternatively you can write one of your own using a set of nested loops.

Sorry... Would you mind giving me more infomation??

thx!

Bjarne Stroustrup gives this as an example in 'The C++ Programming Language':

Code:

---

#include <iostream>
#include <algorithm>
using namespace std;

int main() {
    char v[] = "abcd";
    cout << v << '\t';
    while(next_permutation(v, v+4)) {
        cout << v << '\t';
    }
}

---