Problem:
 Score : 200 points    Problem Statement Given are strings S and T . Consider changing S to T by repeating the operation below. Find the minimum number of operations required to do so.  Operation: Choose one character of S and replace it with a different character.      Constraints  S and T have lengths between 1 and 2\times 10^5 (inclusive).  S and T consists of lowercase English letters.  S and T have equal lengths.         Input Input is given from Standard Input in the following format:  S  T       Output Print the answer.        Sample Input 1 cupofcoffee
cupofhottea      Sample Output 1 4  We can achieve the objective in four operations, such as the following:   First, replace the sixth character c with h .  Second, replace the eighth character f with t .  Third, replace the ninth character f with t .  Fourth, replace the eleventh character e with a .        Sample Input 2 abcde
bcdea      Sample Output 2 5       Sample Input 3 apple
apple      Sample Output 3 0  No operations may be needed to achieve the objective.

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

a = 0
for i in range(len(s)):
    if s[i] != t[i]:
        a += 1
print(a)

Solution (Python):
S = input()
T = input()
n=0
for s, t in zip(S, T):
    if s!=t:
        n+=1
print(n)

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

ret = 0

for s, t in zip(S,T):
    if s!=t:
        ret+=1
print(ret)

Solution (Python):
S = input()
T = input()
L = len(S)
S_split = list(S)
T_split = list(T)
count = 0
for i in range(L):
    if S_split[i] !=T_split[i]:
        count += 1

print(count)

Solution (Python):
a = str(input())
b = str(input())

i = 0
for j in range(len(a)):
    if a[j] != b[j]:
        i += 1

print(i)

Solution (Python):
mod = 1000000007
eps = 10**-9


def main():
    import sys
    input = sys.stdin.readline

    S = input().rstrip('\n')
    T = input().rstrip('\n')
    ans = 0
    for s, t in zip(S, T):
        if s != t:
            ans += 1
    print(ans)


if __name__ == '__main__':
    main()

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

x=0
for i in range(len(s)):
    if s[i]!=t[i]:
        x+=1

print(x)

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

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

n = list(n)
m = list(m)
count = 0
for i in range(len(n)):
    if n[i] != m[i]:
        count+=1

print(count)

Solution (Python):
s=input()
t=input()
n=len(s)
cnt=0
for i in range(n):
    if not(s[i]==t[i]):
        cnt+=1        
    else:
        cnt=cnt 
print(cnt)

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

Solution (Python):
S_list = list(input())
T_list = list(input())
cnt = 0



for i in range(len(S_list)):
    if S_list[i] != T_list[i]:
       cnt += 1

print(cnt)

Solution (Python):
s = str(input())
t = str(input())
count=0
for i in range(len(s)):
  if s[i] != t[i]:
    count+=1
print(count)

Solution (Python):

"""
Created on Sat Jun 27 21:02:04 2020

@author: naoki
"""

S = input()
T = input()

count = 0 
for i in range(len(S)):
    if S[i] != T[i]:
        count+=1
print(count)

Solution (Python):
S = input()
T = input()
i = 0
c = 0
X = len(S)
while i < X:
    if T[i] != S[i]:
        c += 1
    i += 1
print(c)

Solution (Python):
a = [input() for i in range(2)]
r = 0
for i in range(len(a[0])):
  if a[0][i] != a[1][i]:
    r += 1
print(r)

Solution (Python):
s=input()
t=input()
c=0
for i in range(0,len(s)):
    if s[i]==t[i]:
        c+=0
    else:
        c+=1
print(c)

Solution (Python):
a = list(input())
b = list(input())
total = 0
for i in range(len(a)):
  if a[i] != b[i]:
    total += 1

print(total)

Solution (Python):
s=input()
s1=input()
c=0;
for i in range(len(s1)):
  if(s1[i]!=s[i]):
    c+=1;
print(c)

Solution (Python):
S = input()
T = input()
L = len(S)
a = [0]*L
for i in range(L):
    if S[i] != T[i]:
        a[i] = 1
print(sum(a))

Solution (Python):
S=input()
T=input()
v=0
for i in range(len(S)):
    if S[i]!=T[i]:
        v+=1
    else:
        pass
print(v)

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

ans=0
for i in range(len(S)):
    if S[i] != T[i]:
        ans+=1

print(ans)

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

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

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

count = 0
for i in range(len(S)):
    if S[i] != T[i]:
        count += 1
        
print(count)

Solution (Python):
a = input()
b = input()
u=zip(a,b)
x=[]
for i,j in u: 
    if i==j:
        x.append("") 
    else: 
        x.append("*")
print (x.count("*"))

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

ans = 0

for i in range(len(S)):
  if S[i] != T[i]:
    ans += 1

print(ans)

Solution (Python):

a = input()
b = input()

ans = 0
for i, v in enumerate(a):
    if a[i] != b[i]:
        ans += 1
print(ans)

Solution (Python):
S = input()
T = input()
kaisu = 0
for i,c in enumerate(S):
    if c!=T[i]:
        kaisu += 1
print(kaisu)

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

n = len(s)
ans = 0
for i in range(n):
  if s[i] == t[i]:
    ans += 0
  else:
    ans += 1
print(ans)

Solution (Python):
S, T = [list(input()) for i in range(2)]
ans = 0
for s, t in zip(S, T):
    if s != t:
        ans += 1
print(ans)

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

Solution (Python):
S = input()
T = input()
c = 0
for i,s in  enumerate(S):
    if s != T[i]:
        c += 1
print(c)

Solution (Python):
S=input()
T=input()
N=len(S)
s=list(S)
t=list(T)
count=0

for i in range(N):
    if s[i]!=t[i]:
        count+=1
print(count)

Solution (Python):

def calculate(S, T):
	count = 0
	for i in range(len(S)):
		if S[i] != T[i]:
			count += 1
	return count
			

S = input()
T = input()

S = list(S)
T = list(T)

print(calculate(S, T))

Solution (Python):
s = input();
t = input();
c = 0;
for i in range(len(s)):
  if(s[i]!=t[i]):
    c+=1;
print(c);

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

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

cnt = 0
if S == T:
    print(cnt)
    exit()

for i in range(len(S)):
    if S[i] != T[i]:
        cnt += 1
print(cnt)

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

Solution (Python):
s1 = input()
s2 = input()
count = 0
for i in range(len(s1)):
    if s1[i] != s2[i]:
        count += 1
print(count)

Solution (Python):
s = str(input())
t = str(input())
count = 0
for i in range(len(s)):
    if s[i] != t[i]:
        count += 1
        
print(count)

Solution (Python):
def change(s,t):
  n = len(s)
  count=0
  for i in range(n):
    if s[i]!=t[i]:
      count+=1
      
  return count	

s = input()
t = input()
print(change(s,t))

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

Solution (Python):
import sys

a = sys.stdin.readline().strip()
b = sys.stdin.readline().strip()


ans = sum(1 for c, d in zip(a, b) if c != d)
print(ans)

Solution (Python):
"""
AtCoder :: Beginner Contest 172 :: B :: Minor Change
https://atcoder.jp/contests/abc172/tasks/abc172_b
"""
import sys


def solve(S, T):
    """Solve puzzle."""
    return sum(s != t for s, t in zip(S,T))


def main():
    """Main program."""
    S = sys.stdin.readline().strip()
    T = sys.stdin.readline().strip()
    print(solve(S, T))


if __name__ == '__main__':
    main()

Solution (Python):
S = input()
T = input()
count = 0
for (s, t) in zip(S, T):
    if(s != t):
        count += 1
print(count)

Solution (Python):
S = input()
T = input()
f = 0

for i in range(len(S)):
    if S[i] != T[i]:
        f = f + 1

print(f)

Solution (Python):
S = [str(x) for x in list(input())]
T = [str(x) for x in list(input())]
num = 0
for i in range(len(S)):
  if(S[i] != T[i]):
    num += 1
print(num)

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

Solution (Python):
S = input()
T = input()
ans = 0
slen = len(S)

for i in range(int(slen)):
    if S[i] == T[i]:
        pass
    else:
        ans += 1
  
print(ans)

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

count = 0
for i in range(len(S)):
    if S[i] != T[i]:
        count += 1

print(count)

Solution (Python):
def main():
    s = input()
    t = input()
    count = 0
    for i in range(len(s)):
        if s[i] != t[i]:
            count += 1
    print(count)


main()

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

count = 0
for ss, tt in zip(s, t):
  if ss != tt:
    count += 1

print(count)

Solution (Python):


s = list(str(input()))
t = list(str(input()))

cnt = 0

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

print(cnt)

Solution (Python):
import sys 
read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines
S = readline().decode().rstrip()
T = readline().decode().rstrip()
count = 0
for i in range(len(S)):
    if S[i] != T[i]:
        count+=1
print(count)

Solution (Python):
S=list(map(str,input()))
T=list(map(str,input()))
cnt=0
for i in range(len(S)):
  
  if S[i]!=T[i]:
    cnt=cnt+1
print(cnt)

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

Solution (Python):
def resolve():
    s = list(input())
    t = list(input())
    count = 0
    for i in range(len(s)):
        if s[i] != t[i]:
            count = count+1
    print(count)
resolve()

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

Solution (Python):
a = [input() for l in range(0,2)]

a1 = a[0]
a2 = a[1]

s = 0
for i in range(0,len(a1)):
    if a1[i] != a2[i]:
        s = s+1
print(s)

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

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

count = 0
change = 0

for i in range(len(a)):
    if a[count] == b[count]:
        count += 1
    else:
        change += 1
        count += 1
    
print(change)

Solution (Python):
s = str(input())
t = str(input())
ans = 0
for i in range(len(s)):

    if s[i] != t[i]:
        ans += 1


print(ans)

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

Solution (Python):
s = list(input())
t = list(input())
cnt = 0
for i, char in enumerate(s):
    if char != t[i]:
        cnt += 1
print(cnt)

Solution (Python):
S=list(map(str,input()))
T=list(map(str,input()))
ans=0
for i in range(len(S)):
    if S[i]!=T[i]:
        ans+=1
print(ans)

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

count = 0
for i in range(len(S)):
    if S[i] != T[i]:
        count += 1
        
print(count)

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

Solution (Python):
a= input()
b= input()
result=0

for i in range(len(a)):
    if a[i]!=b[i]:
        result=result+1

print(result)

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

Solution (Python):








def solve(S, T):
    ans = 0
    for i in range(len(S)):
        if S[i] != T[i]:
            ans += 1
    print(ans)


if __name__ == '__main__':
    S = input()
    T = input()
    
    
    
    
    solve(S, T)

Solution (Python):
S=input()
T=input()
cc=0
for i in range(len(S)):
    cc+=int(S[i]!=T[i])

print(cc)

Solution (Python):
S = input()
T = input()
c = 0

for i in range(len(S)):
  if S[i] != T[i]:
    c += 1
else:
  print(c)

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

Solution (Python):
import sys
import numpy as np

s, t = map(list, open(0).read().split())
print(np.sum(~(np.array(s) == np.array(t))))

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

Solution (Python):
import logging

logging.basicConfig(level=logging.INFO)
logging.info('info')


def main():
    S = input()
    T = input()
    logging.info("hello")

    counter = 0

    for (s, t) in zip(S, T):
        if s != t:
            counter += 1

    print(counter)

if __name__ == "__main__":
    main()

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

Solution (Python):
s = input()
t = input()
count = 0
for k in range(len(s)):
  if s[k] != t[k]:
    count += 1
    
print(count)

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

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

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

count = 0

for i in range(len(s)):
  if s[i] != t[i]:
    count += 1

print(count)

Solution (Python):

s = input()
t = input()
ans = 0
for i in range(len(s)):
    if s[i] != t[i]:
        ans = ans + 1
print(ans)

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

Solution (Python):
import numpy as np
S = input()
T = input()

a = [1 if S[i]!=T[i] else 0 for i in range(len(S))]
print(np.sum(a))

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

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

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

cnt = 0
for i in range(len(S)):
    if S[i] != T[i]:
        cnt += 1

print(cnt)

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

count = 0

for i in range(len(s)):
    if s[i] != t[i]:
        count += 1

print(count)

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

postion = 0
ansewr = 0

for i in S:
    if i != T[postion]:
        ansewr += 1
        
    postion += 1

print(ansewr)

Solution (Python):
ans = 0
for (s_i,t_i) in zip(input(),input()):
	if s_i != t_i:
		ans += 1
print(ans)

Solution (Python):
import difflib

a = input()
b = input()

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

print(count)

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

Solution (Python):
s = input()
t = input()
cnt = 0
for ss, ts in zip(s,t):
    if ss != ts:
        cnt += 1
print(cnt)

Solution (Python):
S = list(input())
T = list(input())
result = 0
for i in range(len(S)):
    if S[i] != T[i]:
        result += 1
    else:
        pass
print(result)

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

a = int(0)
for i in range(len(t)):
    if s[i] != t[i]:
          a +=1
print(a)

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

ans = 0
for (i,j) in zip(s,t):
  if i != j:
    ans += 1
print(ans)

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

cnt = 0
for i in range(len(S)):
    if S[i] != T[i]:
        cnt += 1
        
print(cnt)

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

ans = 0
for i in range(len(s)):
    if s[i] != t[i]:
        ans += 1

print(ans)

Solution (Python):
s = str(input())
t = str(input())
count = 0
for i in range(len(s)):
    if s[i] != t[i]:
        count += 1
print(count)

Solution (Python):
s = input()
t = input()
cnt=0
for p,q in zip(s,t):
    if p != q:
        cnt+=1
print(cnt)

Solution (Python):
s=input()
t=input()
a=[0]*91
ans=0
b=[0]*91
for i in range(0,len(s)):
    if s[i]!=t[i]:
        ans+=1
print(ans)

Solution (Python):
S=list(input())
T=list(input())
n=len(S)
ans=0
for i in range(n):
  if S[i]!=T[i]:
    ans+=1
print(ans)

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

c=0

for i in range(len(s)):
    if s[i]!=t[i]:
        c+=1

print(c)

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

ans = int()
for i in range(len(s)):
  if s[i]!=t[i]:
    ans += 1
    continue


print(ans)

Solution (Python):
s = input()
t = input()
ans = 0

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

print(ans)

Solution (Python):
S=str(input())
T=str(input())
       
ans = 0

for i in range(len(S)):
  if S[i]==T[i]:
    pass
  else:
    ans+=1
    
print(ans)

Solution (Python):

s = input()
t = input()
ct = 0

for i in range(len(s)):
    if s[i] != t[i]:
        ct +=1
print(ct)

Solution (Python):

s = input()
t = input()

cnt = 0

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

print(cnt)

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

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

ans = 0

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

print(ans)

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

Solution (Python):
S = input()
T = input()
count = 0
for (s,t) in zip(S,T):
    if s != t:
        
        count += 1

print(count)

Solution (Python):
S=list(input())
T=list(input())
ans=0

for i in range(len(S)):
  if S[i] != T[i]:
    ans+=1

print(ans)

Solution (Python):
S=input()
T=input()
N=len(S)
ans=0

for n in range(N):
    if S[n]!=T[n]:
        ans+=1

print(ans)

Solution (Python):
str1 = input()
str2 = input()
cnt = 0

for i in range(len(str1)):
    if str1[i] != str2[i]:
        cnt += 1

print(cnt)

Solution (Python):
str1 = input()
str2 = input()

ans = 0
for i, j in zip(str1, str2):
  if i != j:
    ans += 1
    
print(ans)

Solution (Python):
s = input().rstrip()
t = input().rstrip()

ans = 0

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

print(ans)

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

ans = 0
for i, c in enumerate(s):
    if c != t[i]:
        ans += 1

print(ans)

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

Solution (Python):
s = input()
t = input()
cnt = 0
for si, ti in zip(s,t):
    if si != ti:
        cnt += 1
print(cnt)

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

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

cnt = 0
for i in range(len(s)):
    if s[i] != t[i]:
        cnt += 1

print(cnt)

Solution (Python):
s = input()
t = input()
l = len(s)
c = 0
for i in range(l):
    if s[i] != t[i]:
        c += 1
print(c)

Solution (Python):

import sys;input = sys.stdin.readline
inp,ip = lambda :int(input()),lambda :[int(w) for w in input().split()]

s = input().strip()
t = input().strip()
n = len(s)
ans = 0
for i in range(n):
    if s[i] != t[i]:
        ans += 1
print(ans)

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

N = len(S)

count = 0
for i in range(N):
  if S[i] != T[i]:
    count = count + 1
  else:
    None
    
print(count)

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

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

print(count)

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

n=len(S)
for i in range(n):
  if S[i]==T[i]:
    n-=1
print(n)

Solution (Python):


import sys

def main():
    s = input()
    t = input()
    counter=0

    for a,b in zip(s,t):
        if a!=b:
            counter+=1
    print(counter)

if __name__ == "__main__":
    main()

Solution (Python):

S = input()
T = input()
count = 0
for i in range(len(S)):
  if S[i] != T[i]:
    count += 1
print(count)

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

Solution (Python):
s = input()
t = input()
ans = 0

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

Solution (Python):
def main():
    S = str(input())
    T = str(input())
    cnt = 0
    for i in range(len(S)):
        if S[i] != T[i]:
            cnt += 1
    print(cnt)
if __name__ == '__main__':
    main()

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

count = 0
for i in range(len(S)):
    if S[i] != T[i]:
        count += 1
print(count)

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

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

count = 0
for a1, a2 in zip(s,t):
    if a1 != a2:
        count += 1

print(count)

Solution (Python):
def replacing(S,T):
  count=0
  for i in range(len(S)):
    if S[i]!=T[i]:
      count+=1
  return count
S=input()
T=input()
print(replacing(S,T))

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

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

diff = 0
for i in range(len(S)):
    diff += (S[i] != T[i])

print(diff)

Solution (Python):
s = input()
t = input()
n = len(s)
count = 0

for i in range(n):
    if s[i] != t[i]:
        count += 1

print(count)

Solution (Python):
S=raw_input()
T=raw_input()
res=0
for i in xrange(len(S)):
  if T[i]!=S[i]:
    res+=1
print res

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

Solution (Python):
import sys,copy,bisect,itertools,heapq,math
from heapq import heappop,heappush,heapify
from collections import Counter,defaultdict

s = list(input())
t = list(input())
c = 0
for i in range(len(s)):
    if s[i] != t[i]:
        c+=1

print(c)

Solution (Python):
S = input()
T = input()
n = len(S)
ans = 0
for i in range(n) :
    if S[i] != T[i] :
        ans += 1
print(ans)

Solution (Python):
S=input()
T=input()
cnt=0
for s,t in zip(S,T):
    if s!=t:
        cnt+=1
print(cnt)

Solution (Python):
def edit_distance(S, T):

    NS = len(S)
    NT = len(T)

    ans = 0
    for s,t in zip(S, T):
        if s != t:
            ans += 1

    return ans

S = input().rstrip()
T = input().rstrip()

print(edit_distance(S, T))

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

Solution (Python):
S = input()
T = input()
M = len(S)
ans = 0
for i in range(M):
    if S[i] != T[i]:
        ans += 1
print(ans)

Solution (Python):
s = input()
t = input()
ans = 0
if s == t:
	print(0)
else:
	for index,ss in enumerate(s):
		if t[index] != ss:
			ans += 1
	print(ans)

Solution (Python):
import sys


import math



import numpy as n



def main():


    S = input()
    T = input()

    ans = 0
    for i in range(len(S)):
        if S[i] == T[i]:
            ans += 1

    print(len(S) - ans)

if __name__ == "__main__":
    main()

Solution (Python):


S = input()
T = input()


ans = 0
for s, t in zip(S, T):
    ans += (s != t)


print(ans)

Solution (Python):
s = input()
t = input()
ans=0
cnt=0
for check in s:
    if t[cnt] == check:
        cnt+=1
    else:
        ans+=1
        cnt+=1
print(ans)

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

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

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

count = 0

for ss, tt in zip(s,t):
  if ss != tt:
    count +=1
    
print(count)

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

count = 0
for i in range(len(S)):
  if S[i] != T[i]:
    count += 1
print(count)

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

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

print(count)

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

cnt = 0
for i in range(len(S)):
    if S[i] != T[i]:
        cnt += 1

print(cnt)

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

ans = 0
for i in range(len(S)):
    if S[i] != T[i]:
        ans += 1

print(ans)

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

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

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

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

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

co = 0
for i in range(len(s)):
    if s[i] != t[i]:
        co +=1

print(co)

Solution (Python):
import numpy as np

s = np.array(list(input()))
t = np.array(list(input()))
ans = np.count_nonzero(s!=t)
print(ans)

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

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

Solution (Python):


import sys,copy,bisect,itertools,heapq,math
from heapq import heappop,heappush,heapify
from collections import Counter,defaultdict

s = list(input())
t = list(input())
c = 0
for i in range(len(s)):
    if s[i] != t[i]:
        c+=1

print(c)

Solution (Python):
from sys import stdin
input = stdin.readline


def main():
  S = input()[:-1]
  T = input()[:-1]

  num_op = 0
  for s, t in zip(S, T):
    if not s == t:
      num_op += 1

  print(num_op)


if(__name__ == '__main__'):
  main()

Solution (Python):
import math
import sys

S = list(input())
T = list(input())

count = 0
for i in range(len(S)):
    if S[i] != T[i]:
        count = count + 1

print(count)

Solution (Python):
from collections import deque


S = list(input())
T = list(input())



dqS = deque(S)
dqT = deque(T)

cnt = 0

while dqS:
    tempS = dqS.popleft()
    tempT = dqT.popleft()
    if tempS != tempT:
        cnt += 1

print(cnt)

Solution (Python):
s1=input() 
s2=input() 
ans=sum(s1[i]!=s2[i] for i in range(len(s1))) 
print(ans)

Solution (Python):
import sys
def input(): return sys.stdin.readline().rstrip()


from collections import deque  
def main():
    s = input()
    t = input()
    l = len(s)
    even_list = [1 for i in range(l) if t[i] != s[i]]
    print(len(even_list))

if __name__=='__main__':
    main()

Solution (Python):
def ST(s,t):
    res = 0
    for i in range(len(s)):
        if s[i] != t[i]:
            res += 1
    return res

if __name__ == "__main__":
    s = input()
    t = input()
    print(ST(s,t))

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

Solution (Python):
import bisect,collections,copy,heapq,itertools,math,numpy,string
import sys
from decimal import Decimal
def I(): return int(sys.stdin.readline().rstrip())
def LI(): return list(map(int,sys.stdin.readline().rstrip().split()))
def S(): return sys.stdin.readline().rstrip()
def LS(): return list(sys.stdin.readline().rstrip().split())


s=S()
t=S()

l = len(s)
j=0
if s != t:
    for i in range(l):
        if s[i]!=t[i]:
            j+=1
print(j)

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

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

t = 0

for i in range(len(S)):
    if S[i] != T[i]:
        t += 1

print(t)

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

cnt = 0

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

Solution (Python):
from sys import stdin
input=lambda : stdin.readline().strip()
from math import ceil,sqrt,factorial,gcd
from collections import deque
s=input()
t=input()
count=0
for i in range(len(s)):
	if s[i]!=t[i]:
		count+=1
print(count)

Solution (Python):
S=str(input())
T=str(input())
x=0
for i in range(len(S)):
    if(S[i]!=T[i]):
        x +=1
print(x)

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

nn=len(s)
count=0
for i in range(0,nn):
  if (s[i] != t[i]): count+=1

print(count)

Solution (Python):
S=input();
T=input();
n=0;
for i in range(len(S)):
  if not S[i]==T[i]:
    n=n+1;
print(n)

Solution (Python):
s = str(input())
t = str(input())
count = 0
for i in range(len(s)):
  if s[i] != t[i]:
    count += 1
print (count)

Solution (Python):
S = input()
T = input()
s=[]
for i in S:
    s.append(i)
t=[]
for j in T:
    t.append(j)
ans = 0
for k in range(len(s)):
  if s[k] != t[k]:
    ans += 1
print(ans)

Solution (Python):
import sys

if __name__ == '__main__':
    S = sys.stdin.readline().rstrip()
    T = sys.stdin.readline().rstrip()

    n = 0
    for s, t in zip(S, T):
        if s != t:
            n += 1
    print(n)

Solution (Python):
a=[input() for i in range(2)]

s=a[0]
t=a[1]

s=list(s)
t=list(t)

count=0

for i in range(len(s)):
	if s[i]!=t[i]:
		s[i]=t[i]
		count+=1

print(count)

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

count = 0
n = len(s)

for i in range(n):
    if s[i] != t[i]:
        count += 1

print(count)

Solution (Python):
def main():
        S = list(input())
        T = list(input())
        ans = 0

        for i in range(len(S)):
                if S[i]!=T[i]:
                        ans+=1

        return ans

if __name__=="__main__":
        ans = main()
        print(ans)

Solution (Python):
s = list(input())
t = list(input())
ans = 0

if s == t:
    print(ans)
    exit()
for i in range(len(s)):
    if s[i] != t[i]:
        s[i] = t[i]
        ans += 1
print(ans)

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

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

Solution (Python):

import sys
input = sys.stdin.readline

def I(): return int(input())
def MI(): return map(int, input().split())
def LI(): return list(map(int, input().split()))


s = input().rstrip()
t = input().rstrip()
result = 0
for i in range(len(s)):
    if s[i] != t[i]:
        result += 1
        
print(result)

Solution (Python):
S, T = input(), input()


count = 0
for i, j in zip(S, T):
  if i != j:
    count += 1

print(count)

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

Solution (Python):
S = input()
T = input()
sl, tl = [], []
for s, t in zip(S, T):
    sl.append(ord(s))
    tl.append(ord(t))
ans = 0
for s, t in zip(sl, tl):
    if s != t:
        ans += 1
print(ans)

Solution (Python):
I = [input() for i in range(2)]
S = I[0]
T = I[1]
L = len(S)

C = 0
for l in range(L):
    if S[l] != T[l] :
        C = C + 1

print(C)

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

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

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

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

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

print(count)

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

ans = 0

for i in range(len(S)):
    if S[i] != T[i]:
        ans += 1

print(ans)

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

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

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

ans = 0
for i, j in zip(s, t):
    if i != j:
        ans += 1
print(ans)

Solution (Python):
S = list(input())
T = list(input())
i = 0
flag = 0

for s in S:
    if T[i] != s:
        flag += 1
    i += 1

print(flag)