Write a program to generate all possible permutations and combinations of a given string.

Question

Accepted Answer

This program generates all possible permutations and combinations of a given string.

Use recursion to generate permutations and combinations.
Start with an empty result array and an empty prefix string.
For each character in the input string, append it to the prefix and recursively generate permutations and combinations for the remaining characters.
Add the prefix to the result array.
Repeat the process for all characters in the input string.
Return the result array.

Accepted Answer

# IN python 3.6

#Function to print permutations of a string

# This function takes three parameters:

# 1. String

# 2. Starting index of the string

# 3. Ending index of the string.

def permute(a, l, r):

if l==r:

print toString(a)

else:

for i in xrange(l,r+1):

a[l], a[i] = a[i], a[l]

permute(a, l+1, r)

a[l], a[i] = a[i], a[l] # backtrack

# Driver program to test the above function

string = "ABC"

n = len(string)

a = list(string)

permute(a, 0, n-1)

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