16 - Day 5 - Poisson Distribution I.py

# ========================
#       Information
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# Direct Link: https://www.hackerrank.com/challenges/s10-poisson-distribution-1/problem
# Difficulty: Easy
# Max Score: 30
# Language: Python

# ========================
#         Solution
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from math import factorial, exp

MEAN = float(input())
K = int(input())

POISSON = ((MEAN ** K) * exp(-MEAN)) / factorial(K)

print("%.3f" % POISSON)