/* This function sorts input string, allocate memory for data (needed for
allLexicographicRecur()) and calls allLexicographicRecur() for printing all
permutations */
void allLexicographic(char *str)
{
int len = strlen (str) ;
// Create a temp array that will be used by allLexicographicRecur()
char *data = (char *) malloc (sizeof(char) * (len + 1)) ;
data[len] = '\0';
// Sort the input string so that we get all output strings in
// lexicographically sorted order
qsort(str, len, sizeof(char), compare);
// Now print all permutaions
allLexicographicRecur (str, data, len-1, 0);
// Free data to avoid memory leak
free(data);
}
/* The main function that recursively prints all repeated permutations of
the given string. It uses data[] to store all permutations one by one */
void allLexicographicRecur (char *str, char* data, int last, int index)
{
int i, len ;
for(len=1;len<2;len++){
for ( i=0; i<len; i++ )
{
// Fix the ith character at index and if this is not the last index
// then recursively call for higher indexes
data[index] = str[i] ;
// If this is the last index then print the string stored in data[]
if (index == last)
printf("%s\n", data);
else // Recur for higher indexes
allLexicographicRecur (str, data, last, index+1);
}}
}
/* The main function that recursively prints all repeated permutations of
the given string. It uses data[] to store all permutations one by one */
void allLexicographicRecur (char *str, char* data, int last, int index)
{
int i, len = strlen(str);
// One by one fix all characters at the given index and recur for the
// subsequent indexes
for ( i=0; i<len; i++ )
{
// Fix the ith character at index and if this is not the last index
// then recursively call for higher indexes
data[index] = str[i] ;
// If this is the last index then print the string stored in data[]
if (index == last)
printf("%s\n", data);
else // Recur for higher indexes
allLexicographicRecur (str, data, last, index+1);
}
}
