// C program to print all permutations with duplicates allowed #include <stdio.h> #include <string.h>
/* Function to swap values at two pointers */ void swap(char *x, char *y) { char temp; temp = *x; *x = *y; *y = temp; }
/* Function to print permutations of string This function takes three parameters: 1. String 2. Starting index of the string 3. Ending index of the string. */ void permute(char *a, int l, int r) { int i; if (l == r) printf("%s\n", a); else { for (i = l; i <= r; i++) { swap((a+l), (a+i)); permute(a, l+1, r); swap((a+l), (a+i)); //backtrack } } }
/* Driver program to test above functions */ int main() { char str[] = "ABC"; int n = strlen(str); permute(str, 0, n-1); return 0; }
def permute_string(str):
if len(str) == 0:
return [”]
prev_list = permute_string(str[1:len(str)])
next_list = []
for i in range(0,len(prev_list)):
for j in range(0,len(str)):
new_str = prev_list[i][0:j]+str[0]+prev_list[i][j:len(str)-1]
if new_str not in next_list:
next_list.append(new_str)
return next_list
def permute_string(str):
if len(str) == 0:
return [”]
prev_list = permute_string(str[1:len(str)])
next_list = []
for i in range(0,len(prev_list)):
for j in range(0,len(str)):
new_str = prev_list[i][0:j]+str[0]+prev_list[i][j:len(str)-1]
if new_str not in next_list:
next_list.append(new_str)
return next_list
print(permute_string(‘ABCD’));
how to remove the duplicate permutations from this?
Copy all the elements of the ArrayList to a Set.