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#1
name=input()
mas=[]
nulls=0
cnt=0
with open(name,'r') as file:
  n=int(file.readline())
  for i in range(n):
    mas.append(int(file.readline()))
    
for i in range(n):
  a=mas[i]
  for j in range(i+1,n):
    b=mas[j]
    m=str(a*b)
    r=len(m)-1
    while m[r]=='0' and r>=0:
      nulls+=1
      r-=1
    if nulls==6: cnt+=1
    nulls=0
     
print(cnt)

#2
name=input()
mas=[]
cnt=0
with open(name,'r') as file:
  n=int(file.readline())
  for i in range(n):
    mas.append(int(file.readline()))

for i in range(n):
  a=mas[i]
  for j in range(i+1,n):
    b=mas[j]
    s=a+b
    m=a*b
    if s%11==0 and m%2310==0:cnt+=1
     
print(cnt)

#3
name=input()
mas=[]
maxx=0
with open(name,'r') as file:
  n,k=map(int,file.readline().split())
  for i in range(n):
    mas.append(int(file.readline()))
    
for i in range(n-k):
  s1=sum(mas[i:i+k])
  for j in range(i+k,n-k):
   s2=sum(mas[j:j+k])
   s=s1+s2
   #print(s1,s2,s)
   if s%68==0 and s>maxx: maxx=s
print(maxx)

#8
name=input()
s=0
mins=10000000000
dict={}
with open(name,'r') as file:
  n=int(file.readline())
  for i in range(n):
    x,y=map(int,file.readline().split())
    dict[x]=y
print(dict)
for i in dict.keys():
  for j in dict.keys():
    s+=abs(i-j)*dict[j]
  if (s<mins) or (s==mins and i<x):
    x=i
    mins=s
  s=0
print(x,mins)

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