Problem:
 Score : 100 points    Problem Statement Snuke has a grid consisting of three squares numbered 1 , 2 and 3 .
In each square, either 0 or 1 is written. The number written in Square i is s_i .  Snuke will place a marble on each square that says 1 .
Find the number of squares on which Snuke will place a marble.      Constraints  Each of s_1 , s_2 and s_3 is either 1 or 0 .         Input Input is given from Standard Input in the following format:  s_{1}s_{2}s_{3}       Output Print the answer.        Sample Input 1 101      Sample Output 1 2   A marble will be placed on Square 1 and 3 .        Sample Input 2 000      Sample Output 2 0   No marble will be placed on any square.

Solution (Python):
n = int(input())

count = 0
if int(n / 100) == 1:
    count += 1
    n = n % 100
else:
    pass

if int(n / 10) == 1:
    count += 1
    n = n % 10
else:
    pass

if n == 1:
    count += 1
else:
    pass

print(count)

Solution (Python):
s = input()
print(s.count('1'))

Solution (Python):
s = input()
print(s.count('1'))

Solution (Python):
S = input()
print(S.count("1"))

Solution (Python):
print(input().count("1"))

Solution (Python):
s=input()
print(s.count('1'))

Solution (Python):
s = input()
ans = 0
for i in range(3):
    if s[i] == "1":
        ans += 1
print(ans)

Solution (Python):
a = list(input())
print(a.count('1'))

Solution (Python):
print(input().count("1"))

Solution (Python):
s = input().split()
count = 0

for i in range(len(s[0])):
  if(s[0][i] == '1'):
    count += 1
    
print(count)

Solution (Python):
print(input().count('1'))

Solution (Python):
s = input()

print(s.count('1'))

Solution (Python):
n = input()
result = 0
if n[0] == '1':
  result += 1
if n[1] == '1':
  result += 1
if n[2] == '1':
  result += 1
print(result)

Solution (Python):
n = input()
print(sum([int(i) for i in n]))

Solution (Python):
print(input().count("1"))

Solution (Python):
s = input()
answer = s.count('1')
print(answer)

Solution (Python):
print(input().count("1"))

Solution (Python):
print(sum([i=="1" for i in input()]))

Solution (Python):
a = list(input())
ans = 0
for x in a:
    ans += int(x)

print(ans)

Solution (Python):
print(input().count("1"))

Solution (Python):
n=input()
c=0
if n[0]=="1":
    c+=1
if n[1]=="1":
    c+=1
if n[2]=="1":
    c+=1
print(c)

Solution (Python):
s=list(input())
print(s.count("1"))

Solution (Python):
S = str(input())

count = 0
if S[0] == '1':
    count += 1
if S[1] == '1':
    count += 1
if S[2] == '1':
    count += 1

print(count)

Solution (Python):
print(input().count("1"))

Solution (Python):
s = input()
print(s.count('1'))

Solution (Python):
s1 = input()
print(s1.count('1'))

Solution (Python):
x=input()

x=x.count("1")

print(x)

Solution (Python):
s = input()
l = list(s)
print(l.count('1'))

Solution (Python):
s=input()
print(s.count("1"))

Solution (Python):

a = input()
count = 0
for i in range(3):
	if a[i] == str(1):
		count += 1
	else:
		pass
print(count)

Solution (Python):
s=input()
ans=0
for i in range(len(s)):
    if s[i]=="1":
        ans+=1
print(ans)

Solution (Python):
s = str(input().split())
print(s.count("1"))

Solution (Python):
print(input().count('1'))

Solution (Python):
a=input()

print(a.count("1"))

Solution (Python):
print(input().count('1'))

Solution (Python):
k = input()

l = 0
for t in range(len(k)):
    if k[t] == '1':
        l += 1
print(l)

Solution (Python):
k = input()

l = 0
for t in range(len(k)):
    if k[t] == '1':
        l += 1
print(l)

Solution (Python):
abc = input()
print(abc.count('1'))

Solution (Python):
print(sum(map(int, input().strip())))

Solution (Python):
print(input().count("1"))

Solution (Python):
abc = input()
print(abc.count('1'))

Solution (Python):
n=input()
x=int(n[0])+int(n[1])+int(n[2])
print(x)

Solution (Python):
s = input()
print(s.count('1'))

Solution (Python):
s = input()
print(int(s[0])+int(s[1])+int(s[2]))

Solution (Python):
print(sum([int(n) for n in input()]))

Solution (Python):
s=input()
print(s.count("1"))

Solution (Python):
s=input()
print(int(s[0])+int(s[1])+int(s[2]))

Solution (Python):


s1, s2, s3 = input()

print("{}".format(int(s1)+int(s2)+int(s3)))

Solution (Python):
print(input().count("1"))

Solution (Python):
a,b,c=map(int,input())
d=a+b+c
print(d)

Solution (Python):
list = input()
count = 0
for x in list:
    if x == "1":
        count += 1
print (count)

Solution (Python):
a = input()

sum = 0
for s in a :
    sum += int(s) 

print(sum)

Solution (Python):
print(input().count("1"))

Solution (Python):
inputStr = input()
score = 0
for i in range(len(inputStr)):
    if inputStr[i:i+1] == "1":
        score +=1
print(score)

Solution (Python):
li = list(map(int,list((input()))))
print(li.count(1))

Solution (Python):
a = input()
a = int(a)
if a==111:
  print("3")
elif a==101 or a==110 or a==11:
  print("2")
elif a ==0:
  print("0")
else:
  print("1")

Solution (Python):

import sys
import math
input = sys.stdin.readline

s = input()
print(s.count('1'))

Solution (Python):
s = input()
count = 0
for c in s:
  if c == '1':
    count += 1
    
print(count)

Solution (Python):
S = input()
result =0
for i in S:
    if i == str(1):
        result += 1
print(result)

Solution (Python):
from sys import stdin

list = stdin.readline().rstrip()

result = 0
for i in range(0, 3):
    if(list[i]=='1'):
        result += 1

print(result)

Solution (Python):
if __name__ == '__main__':
    line = str(input())
    count = 0
    if line[0] == '1':
        count += 1
    if line[1] == '1':
        count += 1
    if line[2] == '1':
        count += 1
    print(count)

Solution (Python):
str1 = input()
sum1 = int(str1[0]) +  int(str1[1]) + int(str1[2]) 
print(str(sum1))

Solution (Python):
s=input()

print(s.count('1'))

Solution (Python):
x = list(input())
cnt = 0
for i in range(3):
    if(x[i] == '1'):
        cnt += 1
print(cnt)

Solution (Python):
s=str(input())
ans=0
for i in s:
  if i=="1":
    ans+=1
print(ans)

Solution (Python):


n = input()
print(sum(list(map(int, str(n)))))

Solution (Python):
print(input().count('1'))

Solution (Python):










countup = 0
s = str(raw_input())
for count in s :
    if count == '1':
        countup += 1
    else:
        countup = countup

print countup

Solution (Python):
s=list(input())
ans=0
for i in s:
  if i=="1":
    ans=ans+1
print(ans)

Solution (Python):


grid_info = input()


marble_count = 0

for i in range(len(grid_info)):
  if grid_info[i] == '1':
    marble_count += 1
    
print(marble_count)

Solution (Python):
print(str(sum([int(i) for i in input()])))

Solution (Python):
print(input().count('1'))

Solution (Python):
s = input()
print(s.count("1"))

Solution (Python):
num = input()
print(num.count("1"))

Solution (Python):
d = input()
c = 0
for i in list(range(0,3)):
  if d[i]=='1':
    c = c + 1

print("{}".format(c))

Solution (Python):
a = list(input())

res = 0
for i in range(len(a)):
  res = res + int(a[i])

print(res)

Solution (Python):
allnum = str(input())
x = 0
for i in range(3):
    
  if allnum[i] == "1":
    x = x+1
  else:
    x = x

print(x)

Solution (Python):
print(input().count('1'))

Solution (Python):
s=list(input())
print(s.count("1"))

Solution (Python):
s = input()
count = 0
for c in s:
  if c=='1':
    count+=1
print(count)

Solution (Python):
s = input()

c = 0
if s[0] == "1":
    c += 1
if s[2] == "1":
    c += 1
if s[1] == "1":
    c += 1
print(c)

Solution (Python):
def main():
    s = input()

    counter = 0
    for si in s:
        counter = counter + int(si)

    print(counter)

main()

Solution (Python):
N = input()
cnt = 0
for n in N:
  if n == "1":
    cnt+=1
print(cnt)

Solution (Python):
print(input().count('1'))

Solution (Python):
print(input().count("1"))

Solution (Python):
print(input().count("1"))

Solution (Python):
row = int(input())

a1 = row // 100
a2 = (row - a1 * 100) // 10
a3 = (row - a1 * 100 - a2 * 10)

print(a1 + a2 + a3)

Solution (Python):
from functools import reduce
import math

def main():
    
    
    
    

    
    
    
    
    
    

    
    

    
    
    
    
    
    
    
    
    
    INF = float("inf")

    
    MOD = 10**9+7
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    

    
    
    
    
    a = input()

    print(a.count('1'))
    
if __name__ == '__main__':
    main()

Solution (Python):

s = input()
ans = 0

for i in range(len(s)):
    if s[i] == '1':
        ans += 1

print(ans)

Solution (Python):
if __name__ == '__main__':
    s = str(input())

    print(s.count('1'))

Solution (Python):
from sys import stdin

c = 0
for s in stdin.readline().rstrip():
    if int(s) == 1:
        c = c + 1

print(c)

Solution (Python):
print(input().count('1'))

Solution (Python):
print(sum([int(i) for i in input()]))

Solution (Python):
s = input()
a = [int(i) for i in s]
b = []
for x in range(len(a)):
    if a[x] == 1:
        b.append(1)
print(len(b))

Solution (Python):
S = input()
print(S.count('1'))

Solution (Python):
print(input().count('1'))

Solution (Python):
s=input()
print(s.count("1"))

Solution (Python):
answer = 0
for c in input():
  if c == "1":
    answer += 1
print(answer)

Solution (Python):
S=input()
print(S.count("1"))

Solution (Python):
S=list(input())
print(S.count('1'))

Solution (Python):
print(sum(list(map(lambda x:int(x),list(input().strip())))))

Solution (Python):
S = input()
print(S.count('1'))

Solution (Python):
s = input()
cnt = 0
for i in range(len(s)):
    if s[i]=="1":
        cnt += 1
print(cnt)

Solution (Python):
s=input()

print(s.count("1"))

Solution (Python):
from sys import stdin


def main():
    s = stdin.readline().rstrip()
    print(len([x for x in s if x == '1']))


if __name__ == "__main__":
    main()

Solution (Python):
def main():
    print(input().count('1'))


main()

Solution (Python):



s = input()

cnt = 0
for i in range(3):
  if s[i] == '1':
    cnt += 1

print(cnt)

Solution (Python):
s = input()
print(s.count('1'))

Solution (Python):
s = int(input())
s1 = s//100
s2 = s%100//10
s3 = s%100%10

count = 0

if s1 == 1:
  count = count +1
  
if s2 == 1:
  count = count +1

if s3 == 1:
  count = count +1

print(count)

Solution (Python):
print(input().count('1'))

Solution (Python):
print(input().count("1"))

Solution (Python):
s=input()
count = 0
if s[0] == "1":
    count = count + 1
if s[1] == "1":
    count = count + 1
if s[2] == "1":
    count = count + 1
print(count)

Solution (Python):
print(input().count('1'))

Solution (Python):
input = input()
print(input.count('1'))

Solution (Python):
import sys


def input():
    return sys.stdin.readline()[:-1]








a = str(input())
print(int(a[0])+int(a[1])+int(a[2]))

Solution (Python):
a = input()

snum = 0
if a[0] == '1':
  snum += 1
if a[1] == '1':
  snum += 1
if a[2] == '1':
  snum +=1

print(snum)

Solution (Python):
print(input().count("1"))

Solution (Python):
print(input().count("1"))

Solution (Python):
s = input()
a = [int(c) for c in s]
count = 0
if(a[0] == 1):
  count += 1
if(a[1] == 1):
  count += 1
if(a[2] == 1):
  count += 1
print(count)

Solution (Python):
s = input()

count = 0
for c in s:
    if c == "1":
        count += 1

print(count)

Solution (Python):
marble_place = input()

marble = 0
for character in marble_place:
    if character == '1':
        marble += 1
        
print(marble)

Solution (Python):
s = input()
print(s.count('1'))

Solution (Python):
s=input()
print(s.count("1"))

Solution (Python):
S = list(input())
ans = 0
for i in range(3):
  if S[i] == '1':
    ans += 1
print(ans)

Solution (Python):
s = list(input())
ans = 0
for i in range(3):
  if s[i] == '1':
    ans += 1
print(ans)

Solution (Python):
s = input()
print(s.count('1'))

Solution (Python):
a = input()
b = int(a[0])+int(a[1])+int(a[2])
print(b)

Solution (Python):
str = input()
char_list = list(str)

count=int(char_list[0])+int(char_list[1])+int(char_list[2])
print(count)

Solution (Python):
li = list(input())
c = 0
for i in [0,1,2]:
  if li[i]=='1':
    c = c +1
    
print(c)

Solution (Python):
s = input();
s1 = s[0];
s2 = s[1];
s3 = s[2];
r = 0;
if (s1 == '1'):
    r += 1
if (s2 == '1'):
    r += 1
if (s3 == '1'):
    r += 1
print(r)

Solution (Python):
s = input()
sum = int(s[0])+int(s[1])+int(s[2])
print(sum)

Solution (Python):
s = input()
print(s.count("1"))

Solution (Python):
s=str(input())
print(s.count('1'))

Solution (Python):
S = list(str(input()))
ans = 0
for s in S:
  if s == '1':
    ans += 1
print(ans)

Solution (Python):
s = input()
print(s.count("1"))

Solution (Python):
print(str(input()).count("1"))

Solution (Python):
a, b, c = map(int, input())
print(str(a+b+c))

Solution (Python):
string = input()
counter = 0
if(string[0] == '1'):
    counter += 1
if(string[1] == '1'):
    counter += 1
if(string[2] == '1'):
    counter += 1
print(counter)

Solution (Python):
[a, b, c] = (int(i) for i in list(input()))

counter = 0
for i in [a, b, c]:
    if i == 1:
        counter += 1
        
print(counter)

Solution (Python):
s1, s2, s3 = map(int, input())
A = list([s1, s2, s3])
print(A.count(1))

Solution (Python):
print(input().count("1"))

Solution (Python):
s = raw_input()
a = -1
b = 0
for i in range(3):
    a = a + 1
    if s[a] == "1":
        b = b + 1
print b

Solution (Python):
import sys, os

f = lambda:list(map(int,input().split()))
if 'local' in os.environ :
    sys.stdin = open('./input.txt', 'r')

def solve():
    s = input()
    ans = 0
    for i in s:
        if i == '1':
            ans += 1
    
    print(ans)

solve()

Solution (Python):
print(input().count("1"))

Solution (Python):
a = input()
print(a.count('1'))

Solution (Python):
n = input()
print(n.count("1"))

Solution (Python):
inp = input()

print(len(["A" for x in list(inp) if x == "1"]))

Solution (Python):
s = input()
print(int(s[0]) + int(s[1]) + int(s[2]))

Solution (Python):
a = input()
cnt = 0
for i in a:
  if i == '1':
    cnt+=1
    
print(cnt)

Solution (Python):
s=str(input())
print(s.count('1'))

Solution (Python):
s = input()
print(s.count("1"))

Solution (Python):
s = input()
print(int(s.count("1")))

Solution (Python):
S = input()
li = list(S)
 
ans = 0
for i in range(3):
  if li[i] == "1":
    ans += 1
print(ans)

Solution (Python):
s = input()
t = 0
if s[0] == "1":
    t += 1

if s[1] == "1":
    t += 1

if s[2] == "1":
    t += 1

print(t)

Solution (Python):
test =input()
cnt =0
for r in range(len(test)):
    s = int(test[r])
    if (s%2 == 1):
        cnt +=1

print(cnt)

Solution (Python):
s = input()
print(s.count("1"))

Solution (Python):
print(input().count('1'))

Solution (Python):
print(input().count("1"))

Solution (Python):
S=input()
print(S.count("1"))

Solution (Python):
print(input().count("1"))

Solution (Python):
print(input().count("1"))

Solution (Python):
s = str(input())

print(s.count("1"))

Solution (Python):
s = input()
print(s.count("1"))

Solution (Python):

def read_input():
    s = input()
    d = [int(c) for c in s]
    return d

def submit():
    d = read_input()
    print(sum(d))

if __name__ == '__main__':
    submit()

Solution (Python):



a = input()
ret = 0
for i in range(3):
    if a[i] == '1':
        ret += 1
print(ret)

Solution (Python):
S = int(input())
count=0

if S//100==1:
    count +=1
S=S%100
if S//10==1:
    count +=1
if S%10==1:
    count +=1

print(count)

Solution (Python):
a=input()
print('3' if  a.count('1')==3 else '2' if a.count('1')==2 else '1' if a.count('1')==1 else '0')

Solution (Python):
l=list(input())
print(l.count("1"))

Solution (Python):
print(input().count('1'))

Solution (Python):
s = input()
print(s.count("1"))

Solution (Python):
buf = list(input()).count('1')
print(buf)

Solution (Python):
s = input()
print(s.count('1'))

Solution (Python):
num = str(input())
_num = list(str(num))

print(_num.count("1"))

Solution (Python):
a, b, c = map(int, list(input()))
print(a+b+c)

Solution (Python):
s = input()
print(s.count("1"))

Solution (Python):
s = input()
s1 = int(s[0])
s2 = int(s[1])
s3 = int(s[2])

print(s1 + s2+s3)

Solution (Python):
s = input()

print(s.count('1'))

Solution (Python):
print(input().count('1'))

Solution (Python):
print(input().count('1'))

Solution (Python):
print(input().count("1"))

Solution (Python):
a = str(input())
ans = 0
for i in range(3):
    if a[i] == "1":
        ans = ans + 1
print(ans)

Solution (Python):
a = str(input())
ans = 0
if a[0] == "1":
    ans = ans + 1

if a[1] == "1":
    ans = ans + 1

if a[2] == "1":
    ans = ans + 1

print(ans)

Solution (Python):
s=list(input())
s = [int(i) for i in s]
print(s.count(1))

Solution (Python):
a = str(input())
ans = 0
if a[0] == "1":
    ans = ans + 1

if a[1] == "1":
    ans = ans + 1

if a[2] == "1":
    ans = ans + 1

print(ans)

Solution (Python):
temp=input()
cnt=0
for i in temp:
  if i=='1':
    cnt+=1
print(cnt)

Solution (Python):
a = str(input())
b = 0
for i in range(len(a)):
    if a[i] == "0":
        b += 0
    else:
        b += 1
print(b)

Solution (Python):
s = input()

ans = s.count('1')

print(ans)

Solution (Python):
print(input().count("1"))

Solution (Python):
n = input()
print(n.count('1'))

Solution (Python):
sentence = input()
count = 0
for i in range(len(sentence)):
    if sentence[i] == "1":
        count+=1

print(count)

Solution (Python):
print(input().count("1"))

Solution (Python):
S = input()
print(S.count('1'))

Solution (Python):
a,b,c=map(int,input())
print(a+b+c)

Solution (Python):
a,b,c=map(int,input())
print(a+b+c)

Solution (Python):
s=input()
print(s.count('1'))

Solution (Python):


import sys
import math



Sn = list(str(input()))

print(Sn.count("1"))

Solution (Python):
s = input()
print(s.count('1'))

Solution (Python):
print(input().count("1"))

Solution (Python):
print(input().count('1'))

Solution (Python):
s = [i for i in input()]
print(s.count('1'))

Solution (Python):
data = input()

print(data.count('1'))

Solution (Python):
import numpy as np

s1s2s3=int(input())

count1 = 0

num = []

while s1s2s3 != 0:
    num.append(s1s2s3 % 10)
    s1s2s3 //= 10
num.reverse()

for i in range (len(num)):
    if  num[i-1] == 1:
        count1 = count1 + 1
    else:
        pass

print(count1)

Solution (Python):
s = input()

count = 0
for s_i in s:
	if s_i == "1":
		count += 1

print(count)

Solution (Python):
s = list(input())

def check1(s):
	index,count = (0,0)
	while index < len(s):
		if s[index] == '1':
			count += 1
		index += 1 
	print(count)

check1(s)

Solution (Python):
abc=input()
a=int(abc[0])
b=int(abc[1])
c=int(abc[2])
ans=0
if a==1:
    ans+=1
if b==1:
    ans+=1
if c==1:
    ans+=1
print(ans)

Solution (Python):
n = 0

for i in str(input()):
    if i == '1':
        n += 1

print(n)

Solution (Python):
s = input()
print(s.count('1'))

Solution (Python):
print(input().count("1"))

Solution (Python):
import sys

def main():
    S = input()
    print(counter(S))

def counter(S):
    count = 0
    for s in S:
        if s=='1': count += 1
    return count

if __name__ == '__main__':
    main()

Solution (Python):
s = []
counter = 0
s =  list(str(input()).zfill(3))
for i in range(3):
  if s[i] == '1':
    counter += 1

print(counter)

Solution (Python):
print(list(input()).count('1'))

Solution (Python):
n = input()
print(n.count('1'))

Solution (Python):


s = input()
ans = 0

for i in s:
    if int(i) == 1:
        ans += 1

print(ans)

Solution (Python):
print(input().count("1"))

Solution (Python):
S = input()

ans = 0
for s in S:
    if s == '1':
        ans += 1
print(ans)

Solution (Python):
print(input().count('1'))

Solution (Python):
print(input().count("1"))

Solution (Python):
s1,s2,s3 = map(int,input())
s=[s1,s2,s3]
print(s.count(1))

Solution (Python):
s1,s2,s3=map(int,input())

s_=[s1,s2,s3]

s=s_.count(1)

print(s)

Solution (Python):
a=input()
print(a.count("1"))

Solution (Python):
import collections
def marble(i):
    return collections.Counter(list(i))['1']

if __name__ == '__main__':
    marble_str = input()
    print(marble(marble_str))

Solution (Python):
s=input()
print(s.count("1"))

Solution (Python):
s = [int(i) for i in input()]
count = 0
for i in s:
        if i == 1:
                count += 1
print(count)

Solution (Python):
def main():
    a = input()

    print(a.count('1'))

main()

Solution (Python):
str_list = input()
count = 0
if str_list[0] == '1':
  count = count + 1
if str_list[1] == '1':
  count = count + 1
if str_list[2] == '1':
  count = count + 1
print(count)

Solution (Python):
print(int(input())%9)

Solution (Python):
str = input()
t = 0
 
for s in str:
  t = t + int(s)
  
print(t)

Solution (Python):
str = input()

a = int(str[0])
b = int(str[1])
c = int(str[2])

print(a+b+c)

Solution (Python):
n = input()
cun = 0
for i in n:
    if i == '1':
        cun += 1
print(cun)

Solution (Python):


a,b,c = (int(x) for x in input())
list = [a, b, c]
count = 0
for i in list:
	if i == 1:
		count += 1
print(count)

Solution (Python):
import functools

import os

INF = float('inf')


def inp():
    return int(input())


def inpf():
    return float(input())


def inps():
    return input()


def inl():
    return list(map(int, input().split()))


def inlf():
    return list(map(float, input().split()))


def inls():
    return input().split()


def inpm(line):
    return [inp() for _ in range(line)]


def inpfm(line):
    return [inpf() for _ in range(line)]


def inpsm(line):
    return [inps() for _ in range(line)]


def inlm(line):
    return [inl() for _ in range(line)]


def inlfm(line):
    return [inlf() for _ in range(line)]


def inlsm(line):
    return [inls() for _ in range(line)]


def debug(fn):
    if not os.getenv('LOCAL'):
        return fn

    @functools.wraps(fn)
    def wrapper(*args, **kwargs):
        print('DEBUG: {}({}) -> '.format(
            fn.__name__,
            ', '.join(
                list(map(str, args)) +
                ['{}={}'.format(k, str(v)) for k, v in kwargs.items()]
            )
        ), end='')
        ret = fn(*args, **kwargs)
        print(ret)
        return ret

    return wrapper
print(input().count('1'))

Solution (Python):
print(input().count('1'))

Solution (Python):
s = input()
i = 0
for j in range(len(s)):
    if s[j] == '1': i += 1

print(i)

Solution (Python):
s = input()
print(s.count("1"))

Solution (Python):
s = list(input())
print(s.count("1"))

Solution (Python):
s = list(input())
print(s.count('1'))

Solution (Python):
print(input().count("1"))

Solution (Python):
print(input().count('1'))

Solution (Python):
s = input()
if len(s) != 3:
	print('length')
	exit()

s_list = list(s)

for x in s_list:
	if int(x) < 0 or int(x) > 1:
		exit()

marble = 0
for x in s_list:
	if int(x) == 1:
		marble += 1

print(marble)

Solution (Python):
s = input()
print(s.count('1'))

Solution (Python):
x = input()

if "1" in x:
    print(x.count("1"))
else:
    print(0)

Solution (Python):
print(input().count('1'))

Solution (Python):
s = input()
print(s.count('1'))

Solution (Python):
s = input()
print(s.count('1'))

Solution (Python):
print(input().count("1"))

Solution (Python):
print(input().count("1"))

Solution (Python):
s = input()
word ='1'
print(s.count(word))

Solution (Python):


s = list(input())
count = 0

for i in range(3):
    if s[i] == "1":
        count += 1
print(count)

Solution (Python):
print(input().count('1'))

Solution (Python):
s = input()
print(s.count('1'))

Solution (Python):
S = input()
count = 0
for i in range(len(S)):
  if S[i] == '1':
     count += 1
print(count)

Solution (Python):
S = list(input())

res = 0
for i in range(3):
    if S[i]== '1':
        res += 1
print(res)

Solution (Python):
s = input()
s = list(s)
print(s.count("1"))

Solution (Python):
S = input()
ans = int(S.count("1"))
print(ans)

Solution (Python):
print(input().count("1"))

Solution (Python):

print(input().count('1'))

Solution (Python):
a=input()
print(a.count("1"))

Solution (Python):
a=input()
c=0
for i in range(3):
  if a[i]=="1":
    c+=1
print(c)

Solution (Python):
s = input()
ans = 0
if s[0]=="1":
    ans +=1

if s[1]=="1":
    ans +=1

if s[2]=="1":
    ans += 1

print(ans)

Solution (Python):
a=input()

print(a.count("1"))

Solution (Python):
s = input()
ans = 0
if s[0]=="1":
    ans += 1
    
if s[1]=="1":
    ans += 1

if s[2]=="1":
    ans += 1

print(ans)

Solution (Python):
a = input()
print(a.count("1"))

Solution (Python):
s=input()
output=0

s_list=list(s)

if(s[0]=='1'):
    output+=1
if(s[1]=='1'):
    output+=1
if(s[2]=='1'):
    output+=1

print(output)

Solution (Python):
s = input()
print(s.count('1'))

Solution (Python):



in_list = list(input())
count = 0

 
for string in in_list:
    if int(string)== 1:
        count += 1
print(count)

Solution (Python):
a=input()
print(a.count('1'))

Solution (Python):
a = list(input())
cnt = 0

for i in a:
    if i == "1":
        cnt += 1
print(cnt)

Solution (Python):
num = list(input())

count = 0
for i in num:
  if i == '1':
    count += 1
print(count)

Solution (Python):
S = input()
print(S.count("1"))

Solution (Python):
print(input().count("1"))

Solution (Python):
print(len(input().replace("0", "")))

Solution (Python):
s = input()
print(s.count("1"))

Solution (Python):
B = str(input())
Num_lis = list(B)
flag  = 0
for i in Num_lis:
    if i == "1":
        flag += 1
print(flag)

Solution (Python):
import sys
input = sys.stdin.readline
def ii(): return int(input())
def mi(): return map(int, input().rstrip().split())
def lmi(): return list(map(int, input().rstrip().split()))
def li(): return list(input().rstrip())



S = li()
print(S.count('1'))

Solution (Python):
s = input()
cnt = 0

for i in range(len(s)):
  if s[i] == "1":
    cnt += 1
    
print(cnt)

Solution (Python):

from collections import defaultdict
from collections import deque
from heapq import heappush, heappop
import sys
import math
import bisect
import random
import itertools
sys.setrecursionlimit(10**5)
stdin = sys.stdin
bisect_left = bisect.bisect_left
bisect_right = bisect.bisect_right
def LI(): return list(map(int, stdin.readline().split()))
def LF(): return list(map(float, stdin.readline().split()))
def LI_(): return list(map(lambda x: int(x)-1, stdin.readline().split()))
def II(): return int(stdin.readline())
def IF(): return float(stdin.readline())
def LS(): return list(map(list, stdin.readline().split()))
def S(): return list(stdin.readline().rstrip())
def IR(n): return [II() for _ in range(n)]
def LIR(n): return [LI() for _ in range(n)]
def FR(n): return [IF() for _ in range(n)]
def LFR(n): return [LI() for _ in range(n)]
def LIR_(n): return [LI_() for _ in range(n)]
def SR(n): return [S() for _ in range(n)]
def LSR(n): return [LS() for _ in range(n)]
mod = 1000000007
inf = float('INF')


def A():
    n, a, b = LI()
    print(min(n*a,b))
    return


def B():
    a = S()
    print(a.count("1"))
    return


def C():
    n = II()
    a = list(str(n))
    a = list(map(int,a))
    if not n % sum(a):
        print("Yes")
    else:
        print("No")
    return


def D():
    n = II()
    a = LI()
    ans = 0
    for a_ in a:
        while not a_ % 2:
            ans += 1
            a_ /= 2
    print(ans)
    return


def E():
    return


def F():
    return


def G():
    return


def H():
    return


if __name__ == '__main__':
    B()

Solution (Python):
import re

a = input()

count = 0
for i in range(len(a)):
    if(a[i] == '1'):
        count += 1
print(count)

Solution (Python):
s = input()
print(s.count('1'))

Solution (Python):

from collections import defaultdict
from collections import deque
from heapq import heappush, heappop
import sys
import math
import bisect
import random
def LI(): return list(map(int, sys.stdin.readline().split()))
def I(): return int(sys.stdin.readline())
def LS():return list(map(list, sys.stdin.readline().split()))
def S(): return list(sys.stdin.readline())[:-1]
def IR(n):
    l = [None for i in range(n)]
    for i in range(n):l[i] = I()
    return l
def LIR(n):
    l = [None for i in range(n)]
    for i in range(n):l[i] = LI()
    return l
def SR(n):
    l = [None for i in range(n)]
    for i in range(n):l[i] = S()
    return l
def LSR(n):
    l = [None for i in range(n)]
    for i in range(n):l[i] = LS()
    return l
sys.setrecursionlimit(1000000)
mod = 1000000007


def A():
    n,a,b = LI()
    print(min(n*a,b))
    return


def B():
    s = S()
    print(s.count("1"))
    return


def C():
    return


def D():
    return


def E():
    return


def F():
    return


def G():
    return


def H():
    return


def I_():
    return


def J():
    return


if __name__ == "__main__":
    B()

Solution (Python):
a = input()
b = 0
for i in range(len(a)):
    b += int(a[i])
print(b)

Solution (Python):
print(sum([int(a) for a in input()]))

Solution (Python):
a = input()
count = 0
for i in range(3):
    if a[i-1] == "1":
        count += 1
print(str(count))

Solution (Python):
s = input()
print(s.count('1'))

Solution (Python):
s = input()
print(s.count('1'))

Solution (Python):
s = input()
res = 0
for v in s:
  res += int(v)
print(res)

Solution (Python):

str = input()
total = 0
for s in str:
    total += int(s)
print(total)

Solution (Python):
work = input()
a, b, c = work[:1], work[1:2], work[2:3]

cnt = 0
if a == '1':
    cnt += 1
if b == '1':
    cnt += 1
if c == '1':
    cnt += 1

print(cnt)

Solution (Python):
s=list(str(input()))

print(s.count("1"))

Solution (Python):
print(input().count('1'))

Solution (Python):
s = input()
print(s.count('1'))

Solution (Python):
print(input().count("1"))

Solution (Python):
print(input().count('1'))

Solution (Python):
s = input()
ans = 0
if s[0] == "1":
  ans += 1
if s[1] == "1":
  ans += 1
if s[2] == "1":
  ans += 1
  
print(ans)

Solution (Python):
a = input()
ans = a.count("1")
print(ans)

Solution (Python):

s = input()
print(s.count("1"))

Solution (Python):
s = input()

ans = s.count('1')

print(ans)

Solution (Python):
numbers = input()

num_list = [int(i) for i in numbers]
print(sum(num_list))

Solution (Python):
s = input()
print(s.count("1"))

Solution (Python):
ret = list(filter(lambda x: x==1, map(int, list(input()))))
print(len(ret))

Solution (Python):
s=input()
print(s.count("1"))

Solution (Python):
str=list(input())
s1=int(str[0])
s2=int(str[1])
s3=int(str[2])
print(s1+s2+s3)

Solution (Python):
s = input()
print(s.count("1"))

Solution (Python):
print(input().count("1"))

Solution (Python):
print(input().count("1"))

Solution (Python):
S = input()
cnt = 0
for i in range(3):
  if S[i] == "1":
    cnt += 1
print(cnt)

Solution (Python):
s = int(input())
i = 0
if(s//100==1):
    i = i + 1
    s = s - 100
if(s//10==1):
    i = i + 1
    s = s-10
if(s==1):
    i = i + 1
print(i)

Solution (Python):
s = input()
count = 0
for i in s:
  if i == "1":
    count += 1
print(count)

Solution (Python):
s = input()
counter = 0
if s[0]=='1':
    counter+=1
if s[1]=='1':
    counter+=1
if s[2]=='1':
    counter+=1
print(counter)

Solution (Python):
s = input()
print(s.count('1'))

Solution (Python):
s = input()
b = 0
for i in s:
    if i == "1":
        b += 1
print(b)

Solution (Python):
s = input()
count = 0
for i in s:
    if i == "1":
        count += 1
print(count)

Solution (Python):
s=input()
count=0
for char in s:
  if char == '1':
    count += 1
print(count)

Solution (Python):
value = sum(map(int, list(input())))
print(value)

Solution (Python):
print(input().count("1"))

Solution (Python):
n=input()
print(n.count("1"))

Solution (Python):
a = input()

counter = 0
for i in range(3):
    if int(a[-1-i]) ==  1:
        counter += 1
print(counter)

Solution (Python):
print(input().count('1'))

Solution (Python):
numbers_list = list(map(int, input()))
print(numbers_list.count(1))

Solution (Python):

a = input()
print(a.count('1'))

Solution (Python):
l=list(map(int, input()))
print(l.count(1))

Solution (Python):
s=input()
if s[0]=="0":
    count=0
else:
    count=1
if s[1]=="0":
    count+=0
else:
    count+=1
if s[2]=="0":
    count+=0
else:
    count+=1
print(count)