Consider All lowercase Alphabets of the English language. Here we consider each alphabet from a to z to have a certain weight. The weight of the alphabet a is considered to be 1, b to be 2, c to be 3 and so on until z has a weight of 26. In short, the weight of the alphabet a is 1, and the weight of all other alphabets is the weight of its previous alphabet + 1. 

Now, you have been given a String S consisting of lowercase English characters. You need to find the summation of weight of each character in this String.  

For example, Consider the String aba
Here, the first character a has a weight of 1, the second character b has 2 and the third character a again has a weight of 1. So the summation here is equal to :
 1  + 2 + 1 =  4    

Input Format:
The first and only line of input contains the String S. 

Output Format 
Print the required answer on a single line

Constraints
 1 ≤ |S| ≤ 1000    

SAMPLE INPUT
aba

SAMPLE OUTPUT
4

Explanation

Explanation for the Sample has been given in the Problem Statement.
'''
# Read input from stdin and provide input before running code

#name = raw_input('What is your name?\n')
#print 'Hi, %s.' % name
#'''
#print 'Hello World!'
sum=0
s=raw_input()
for i in s:
	if i=='a':
		sum+=1
	elif i=='b':
		sum+=2
	elif i=='c':
		sum+=3
	elif i=='d':
		sum+=4
	elif i=='e':
		sum+=5
	elif i=='f':
		sum+=6
	elif i=='g':
		sum+=7
	elif i=='h':
		sum+=8
	elif i=='i':
		sum+=9
	elif i=='j':
		sum+=10
	elif i=='k':
		sum+=11
	elif i=='l':
		sum+=12
	elif i=='m':
		sum+=13
	elif i=='n':
		sum+=14
	elif i=='o':
		sum+=15
	elif i=='p':
		sum+=16
	elif i=='q':
		sum+=17
	elif i=='r':
		sum+=18
	elif i=='s':
		sum+=19
	elif i=='t':
		sum+=20
	elif i=='u':
		sum+=21
	elif i=='v':
		sum+=22
	elif i=='w':
		sum+=23
	elif i=='x':
		sum+=24
	elif i=='y':
		sum+=25
	elif i=='z':
		sum+=26
print sum