Buggy python submission (verdict: Runtime Error):
from collections import Counter
h,w=map(int,input().split())
#a=[list(input()) for i in range(w)]
a=[]
flag=True
for i in range(h):
  a+=list(input())
ca=Counter(a)
if h%2==0 and w%2==0:
  for i in ca:
    if ca[i]%4!=0:
      flag=False
      print('No')
      break
  if flag:
    print('Yes')

elif h%2!=0 and w%2!=0:
  yon=(h-1)*(w-1)
  ni=h*w-yon-1
  iti=1
  for i in ca:
    while ca[i]>0
      if ca[i]%4==0 and yon>0:
        ca[i]-=4
        yon-=4
      elif ca[i]%2==0 and ni>0:
        ni-=2
        ca[i]-=2
      elif iti>0:
        iti-=1
        ca[i]-=1
      else:
        break
  if yon==0 and ni==0 and iti==0:
    print('Yes')
  else:
    print('No')
else:
  if h%2==0:
    yon=(h)*(w-1)
  else:
    yon=(h-1)*(w)
  ni=h*w-yon
  for i in ca:
    while ca[i]>0:
      if ca[i]%4==0 and yon>0:
        ca[i]-=4
        yon-=4
      elif ca[i]%2==0 and ni>0:
        ni-=2
        ca[i]-=2
      else:
        break
  if yon==0 and ni==0:
    print('Yes')
  else:
    print('No')
  
  

Fixed submission:
from collections import Counter
h,w=map(int,input().split())
#a=[list(input()) for i in range(w)]
a=[]
flag=True
for i in range(h):
  a+=list(input())
ca=Counter(a)
if h%2==0 and w%2==0:
  for i in ca:
    if ca[i]%4!=0:
      flag=False
      print('No')
      break
  if flag:
    print('Yes')

elif h%2!=0 and w%2!=0:
  yon=(h-1)*(w-1)
  ni=h*w-yon-1
  iti=1
  for i in ca:
    while ca[i]>0:
      if ca[i]%4==0 and yon>0:
        ca[i]-=4
        yon-=4
      elif ca[i]%2==0 and ni>0:
        ni-=2
        ca[i]-=2
      elif iti>0:
        iti-=1
        ca[i]-=1
      else:
        break
  if yon==0 and ni==0 and iti==0:
    print('Yes')
  else:
    print('No')
else:
  if h%2==0:
    yon=(h)*(w-1)
  else:
    yon=(h-1)*(w)
  ni=h*w-yon
  for i in ca:
    while ca[i]>0:
      if ca[i]%4==0 and yon>0:
        ca[i]-=4
        yon-=4
      elif ca[i]%2==0 and ni>0:
        ni-=2
        ca[i]-=2
      else:
        break
  if yon==0 and ni==0:
    print('Yes')
  else:
    print('No')

Buggy python submission (verdict: Time Limit Exceeded):
from collections import Counter
h,w=map(int,input().split())
#a=[list(input()) for i in range(w)]
a=[]
flag=True
for i in range(h):
  a+=list(input())
ca=Counter(a)
if h%2==0 and w%2==0:
  for i in ca:
    if ca[i]%4!=0:
      flag=False
      print('No')
      break
  if flag:
    print('Yes')

elif h%2!=0 and w%2!=0:
  yon=(h-1)*(w-1)
  ni=h*w-yon-1
  iti=1
  for i in ca:
    while ca[i]>0:
      if iti<0:
        break
      if ca[i]%4==0 and yon>0:
        ca[i]-=4
        yon-=4
      elif ca[i]%2==0 and ni>0:
        ni-=2
        ca[i]-=2
      elif iti>0:
        iti-=1
        ca[i]-=1
  if yon==0 and ni==0 and iti==0:
    print('Yes')
  else:
    print('No')
else:
  if h%2==0:
    yon=(h)*(w-1)
  else:
    yon=(h-1)*(w)
  ni=h*w-yon
  for i in ca:
    while ca[i]>0:
      if ca[i]%4==0 and yon>0:
        ca[i]-=4
        yon-=4
      elif ca[i]%2==0 and ni>0:
        ni-=2
        ca[i]-=2
      else:
        break
  if yon==0 and ni==0:
    print('Yes')
  else:
    print('No')
  
  

Fixed submission:
from collections import Counter
h,w=map(int,input().split())
#a=[list(input()) for i in range(w)]
a=[]
flag=True
for i in range(h):
  a+=list(input())
ca=Counter(a)
if h%2==0 and w%2==0:
  for i in ca:
    if ca[i]%4!=0:
      flag=False
      print('No')
      break
  if flag:
    print('Yes')

elif h%2!=0 and w%2!=0:
  yon=(h-1)*(w-1)
  ni=h*w-yon-1
  iti=1
  for i in ca:
    while ca[i]>0:
      if ca[i]%4==0 and yon>0:
        ca[i]-=4
        yon-=4
      elif ca[i]%2==0 and ni>0:
        ni-=2
        ca[i]-=2
      elif iti>0:
        iti-=1
        ca[i]-=1
      else:
        break
  if yon==0 and ni==0 and iti==0:
    print('Yes')
  else:
    print('No')
else:
  if h%2==0:
    yon=(h)*(w-1)
  else:
    yon=(h-1)*(w)
  ni=h*w-yon
  for i in ca:
    while ca[i]>0:
      if ca[i]%4==0 and yon>0:
        ca[i]-=4
        yon-=4
      elif ca[i]%2==0 and ni>0:
        ni-=2
        ca[i]-=2
      else:
        break
  if yon==0 and ni==0:
    print('Yes')
  else:
    print('No')

Buggy python submission (verdict: Time Limit Exceeded):
from collections import Counter
h,w=map(int,input().split())
#a=[list(input()) for i in range(w)]
a=[]
flag=True
for i in range(h):
  a+=list(input())
ca=Counter(a)
if h%2==0 and w%2==0:
  for i in ca:
    if ca[i]%4!=0:
      flag=False
      print('No')
      break
  if flag:
    print('Yes')

elif h%2!=0 and w%2!=0:
  yon=(h-1)*(w-1)
  ni=h*w-yon-1
  iti=1
  for i in ca:
    while ca[i]>0:
      if ca[i]%4==0 and yon>0:
        ca[i]-=4
        yon-=4
      elif ca[i]%2==0 and ni>0:
        ni-=2
        ca[i]-=2
      elif iti>0:
        iti-=1
        ca[i]-=1
  if yon==0 and ni==0 and iti==0:
    print('Yes')
  else:
    print('No')
else:
  if h%2==0:
    yon=(h)*(w-1)
  else:
    yon=(h-1)*(w)
  ni=h*w-yon
  for i in ca:
    while ca[i]>0:
      if ca[i]%4==0 and yon>0:
        ca[i]-=4
        yon-=4
      elif ca[i]%2==0 and ni>0:
        ni-=2
        ca[i]-=2
      else:
        break
  if yon==0 and ni==0:
    print('Yes')
  else:
    print('No')
  
  

Fixed submission:
from collections import Counter
h,w=map(int,input().split())
#a=[list(input()) for i in range(w)]
a=[]
flag=True
for i in range(h):
  a+=list(input())
ca=Counter(a)
if h%2==0 and w%2==0:
  for i in ca:
    if ca[i]%4!=0:
      flag=False
      print('No')
      break
  if flag:
    print('Yes')

elif h%2!=0 and w%2!=0:
  yon=(h-1)*(w-1)
  ni=h*w-yon-1
  iti=1
  for i in ca:
    while ca[i]>0:
      if ca[i]%4==0 and yon>0:
        ca[i]-=4
        yon-=4
      elif ca[i]%2==0 and ni>0:
        ni-=2
        ca[i]-=2
      elif iti>0:
        iti-=1
        ca[i]-=1
      else:
        break
  if yon==0 and ni==0 and iti==0:
    print('Yes')
  else:
    print('No')
else:
  if h%2==0:
    yon=(h)*(w-1)
  else:
    yon=(h-1)*(w)
  ni=h*w-yon
  for i in ca:
    while ca[i]>0:
      if ca[i]%4==0 and yon>0:
        ca[i]-=4
        yon-=4
      elif ca[i]%2==0 and ni>0:
        ni-=2
        ca[i]-=2
      else:
        break
  if yon==0 and ni==0:
    print('Yes')
  else:
    print('No')