CODE EXAMPLE FOR PYTHON

permutation and combination program in python

# Python program to print all permutations with 
# duplicates allowed 
  
def toString(List): 
    return ''.join(List) 
  
# 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. 
def permute(a, l, r): 
    if l==r: 
        print (toString(a))
    else: 
        for i in range(l,r): 
            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) 
  
# This code is contributed by Bhavya Jain