#!/usr/bin/env python3
import sys

file = sys.argv[1]
key = sys.argv[2]

with open(file, "r") as f:
    lines = f.readlines()

wers = []
count = 0

for line in lines:
    if key in line:
        wers.append(float(line.split(key)[-1].lstrip().rstrip()))
        count += 1

mean = sum(wers) / len(wers)
var = sum([(w - mean)**2 for w in wers]) / len(wers)


print("mean", mean)
print("var", var)