import time
import sys 
f=open("in6_9.txt","r")
f1=open("out_9_6_9.txt","w")
start=time.clock()
temp=[]
for i in f:
    temp=i.split(",")
x=(temp[0])
d=(temp[1])
n=(temp[2])
sum=(int(n)/2.0)*(2*(int(x))+(int(n)-1)*(int(d)))
elapsed=time.clock()-start
total=sys.getsizeof(x)+sys.getsizeof(n)+sys.getsizeof(d)+sys.getsizeof(elapsed)+sys.getsizeof(temp)
f1.write("sum of nth arithmetic progression-:"+str(sum)+"\ntime------------------------------:"+str(elapsed)+"\ntotal memory----------------------:"+str(total)+"\nno. of multiplication-------------:"+str(4)+"\nno. of addition-------------------:"+str(2))
f.close()
f1.close()