# Python program to find the number occurring odd number of times using Lambda expression and reduce function

PythonServer Side ProgrammingProgramming

Here given a user input positive integer array. Our task is to find out the number occurring odd number of times.

## Example

Input : A=[2, 4, 7, 7, 4, 2, 2]
Output : 2

## Algorithm

Step 1: Input Array element.
Step 2: Write lambda expression and apply.
Step 3: Reduce function over the input list until a single value is left.
Step 4: Expression reduces the value of a^b into a single value.
Step 5: a starts from 0 and b starts from 1.

## Example Code

# Python program to find the Number
# Occurring Odd Number of Times
# using Lambda expression and reduce function

from functools import reduce
def timeoccurrance(inp):
print ("RESULT ::>",reduce(lambda a, b: a ^ b, inp)))

# Driver program
if __name__ == "__main__":
A=list()
n1=int(input("Enter the size of the List ::"))

print("Enter the Element of List ::")
for i in range(int(n1)):
k=int(input(""))
A.append(k)
timeoccurrance(A)

## Output

Enter the size of the List :: 7
Enter the Element of List ::
1
2
3
2
3
1
3
RESULT ::> 3
Published on 26-Sep-2018 16:42:15