Permutation of String letters: How to remove repeated permutations?

Question

Here is a standard function to print the permutations of characters of a string:

void permute(char *a, int i, int n)
{
   int j;
   if (i == n)
     printf(\         


        

Answer 1

Standard library has what you need:

#include 
#include 
#include 
#include 
using namespace std;

void print_all_permutations(const string& s)
{
    string s1 = s;
    sort(s1.begin(), s1.end()); 
    do {
        cout << s1 << endl;
    } while (next_permutation(s1.begin(), s1.end()));
}

int main()
{
    print_all_permutations("AAB");
}

Result:

$ ./a.out
AAB
ABA
BAA