Problem:
 Score : 100 points    Problem Statement Find the number of ways to choose a pair of an even number and an odd number from the positive integers between 1 and K (inclusive). The order does not matter.      Constraints  2\leq K\leq 100  K is an integer.         Input Input is given from Standard Input in the following format:  K       Output Print the number of ways to choose a pair of an even number and an odd number from the positive integers between 1 and K (inclusive).        Sample Input 1 3      Sample Output 1 2  Two pairs can be chosen: (2,1) and (2,3) .       Sample Input 2 6      Sample Output 2 9       Sample Input 3 11      Sample Output 3 30       Sample Input 4 50      Sample Output 4 625

Solution (Python):
N = int(input())
Even = []
Odd = []
for i in range(1,N+1):
    if i % 2 == 0:
        Even.append(i)
    else:
        Odd.append(i)
print(len(Even) * len(Odd))

Solution (Python):
K=int(input())
i=K//2
if (K%2==0):
    print(i**2)
else:
    print((i**2)+i)

Solution (Python):
K = int(input())
if K % 2 == 0:
    ans = (K/2)*(K/2)
else:
    ans = (K-1)/2 * ((K-1)/2 + 1)

print(int(ans))

Solution (Python):
k=int(input())
print(int(k/2)*int((k+1)/2))

Solution (Python):
k = int(input())
if k%2:
  print((k//2) * (k//2+1))
else:
  print((k//2)**2)

Solution (Python):

K = int(input())

odd = []
even = []
for i in range(1,K+1) :
	if (i % 2 == 1) :
		odd.append(i)
	else :
		even.append(i)

print(len(odd) * len(even))

Solution (Python):
a = (int)(input())
print((int)(a/2)*((int)(a/2)+a%2))

Solution (Python):
import math,string,itertools,fractions,heapq,collections,re,array,bisect,sys,random,time,copy,functools

sys.setrecursionlimit(10**7)
inf = 10**20
eps = 1.0 / 10**13
mod = 10**9+7
dd = [(-1,0),(0,1),(1,0),(0,-1)]
ddn = [(-1,0),(-1,1),(0,1),(1,1),(1,0),(1,-1),(0,-1),(-1,-1)]

def LI(): return [int(x) for x in sys.stdin.readline().split()]
def LI_(): return [int(x)-1 for x in sys.stdin.readline().split()]
def LF(): return [float(x) for x in sys.stdin.readline().split()]
def LS(): return sys.stdin.readline().split()
def I(): return int(sys.stdin.readline())
def F(): return float(sys.stdin.readline())
def S(): return input()
def pf(s): return print(s, flush=True)


def main():
    n = I()
    a = n // 2
    b = n - a

    return a * b


print(main())

Solution (Python):
k = int(input())
print((k//2)*((k+1)//2))

Solution (Python):
k = int(input())
even = k//2
odd = k-even
print(even*odd)

Solution (Python):
K=int(input())
if K%2==0:
  print(int((K/2)*(K/2)))
else:
  print(int(((K+1)/2)*((K-1)/2)))

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

if a % 2 == 0:
    print((a // 2) ** 2)
else:
    print((a//2)*(a//2+1))

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

if K % 2 != 0:
    print(round(((K-1)/2)*((K-1)/2 + 1)))
    exit()

print(round((K/2)**2))

Solution (Python):
num = int(input())
even = int(num / 2)
odd = int(num / 2)

if num % 2 == 1:
    odd = odd + 1
    
print( even*odd )

Solution (Python):
k=input()
print (k/2+k%2)*(k/2)

Solution (Python):
k = int(input())
print(((k + 1) // 2) * (k // 2))

Solution (Python):
from collections import defaultdict, Counter
from itertools import product, groupby, count, permutations, combinations
from math import pi, sqrt
from collections import deque
from bisect import bisect, bisect_left, bisect_right
from string import ascii_lowercase
from functools import lru_cache
import sys
sys.setrecursionlimit(10000)
INF = float("inf")
YES, Yes, yes, NO, No, no = "YES", "Yes", "yes", "NO", "No", "no"
dy4, dx4 = [0, 1, 0, -1], [1, 0, -1, 0]
dy8, dx8 = [0, -1, 0, 1, 1, -1, -1, 1], [1, 0, -1, 0, 1, 1, -1, -1]


def inside(y, x, H, W):
    return 0 <= y < H and 0 <= x < W


def ceil(a, b):
    return (a + b - 1) // b


def main():
    K = int(input())
    a = K // 2
    b = K - a
    print(a * b)


if __name__ == '__main__':
    main()

Solution (Python):
a = int(input())
print(int((a / 2)) * int((a + 1)/2))

Solution (Python):
def pair(k):
    return (k // 2) * (k // 2 + k % 2)

k = int(input())
print(pair(k))

Solution (Python):
n=int(input())
even=n//2
odd=(n+1)//2
print(even*odd)

Solution (Python):
k = int(input())
if k%2 == 0:
    print(int((k/2)*(k/2)))
else:
    print(int(((k-1)/2)*((k+1)/2)))

Solution (Python):
k=int(input())
eve_num= k//2
neg_num= k-eve_num
print(eve_num*neg_num)

Solution (Python):
k = input()
print (k / 2) * (k / 2 + k % 2)

Solution (Python):
def a():
    s=int(input())
    n=0
    for i in range(1,s,2):
        n=n+s-i
    print(n)
a()

Solution (Python):
a = int(input())
print(int(a/2) * int((a+1)/2))

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

odd = (K + 2 - 1) // 2
eve = K // 2

print(odd * eve)

Solution (Python):
k = int(input())
count1 = 0
count2 = 0

for i in range(k):
    if i % 2 != 0:
        count1 += 1
    else:
        count2 += 1

print(count1 * count2)

Solution (Python):
K = int(input())
print(int(K/2) * (int(K/2) + K % 2))

Solution (Python):
def solve(K):
    return (K // 2) * (K - (K // 2))


if __name__ == "__main__":
    K = int(input(""))
    print(solve(K))

Solution (Python):
import math

K=int(input())
result=int(K/2)
if(K%2==0):
    print(result*result)
else:
    print(result*(result+1))

Solution (Python):
k=int(input())
print(k//2*((k+1)//2))

Solution (Python):
N=int(input())
if N%2==0:
  print(int((N/2)**2))
else:
  print(int((N**2-1)/4))

Solution (Python):
k=int(input())
a=int(k/2)
b=int((k+1)/2)
print(a*b)

Solution (Python):
n=int(input())
if n%2==0:
  print(int((n/2)**2))
else:
  print(int(int(n/2)*(int(n/2)+1)))

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

if k%2==0:
    print(int((k/2)*(k/2)))
else:
    print(int((k-1)/2*((k+1)/2)))

Solution (Python):
k=int(input())
if k%2 ==0 :
    print ( (k//2)*(k//2) )
else :
    print ( (1+(k//2))*(k//2))

Solution (Python):
from math import*
k= int(input ())
if (k%2==0):
    print (int((k/2)**2))
else:
    print(int(ceil(k/2)*floor(k/2)))

Solution (Python):
K = int(input())
g_list = []
k_list = []

for i in range(1, K+1):
    if i%2 == 0:
        g_list += [i]
    elif i%2 == 1:
        k_list += [i]

g_len = len(g_list)
k_len = len(k_list)
print(g_len*k_len)

Solution (Python):
K = int(input())
 
if K % 2 == 0:
  print(int(K/2*K/2))
else:
  print(int((K-1)*(K+1)/4))

Solution (Python):
k=int(input())
x=k//2
if k%2==0:
    print(x*x)
else:
    print(x*(x+1))

Solution (Python):
k=int(input())
even=[]
odd=[]
for i in range (1,k+1,1):
    if i%2==0:
        even.append(i)
    else:
        odd.append(i)
result=[(x,y) for x in even for y in odd]
print(len(result))

Solution (Python):
k=int(input())
nomber_of_even_nombers=k//2
nomber_of_odd_nombers=k-nomber_of_even_nombers
nomber_of_wayes=nomber_of_even_nombers*nomber_of_odd_nombers
print(nomber_of_wayes)

Solution (Python):
N = int(input())
E = N // 2
O = N - E
print(E*O)

Solution (Python):
k = int(input())
even=0
odd = 0
for i in range(1,k+1):
  if i % 2 ==0:
    even += 1
  else:
    odd += 1

print(even*odd)

Solution (Python):
k=int(input())
odd=1
even=0
for i in range(2,k+1,1):
    if i%2==1:
        odd+=1
    else:
        even+=1
print(even*odd)

Solution (Python):
k=int(input())
odd=1
even=0
for i in range (2,k+1):
   if i%2==1:
       odd+=1
   else:
       even+=1
print(odd*even)

Solution (Python):
k = input()

l = int(k/2)

print(l*(k-l))

Solution (Python):
k = int(input())
print(int(k / 2) * (k - int(k / 2)))

Solution (Python):
k=int(input())
odd=1 
even=0
for i in range (2,k+1):
   if i%2==0:
       even+=1 
   else:
       odd+=1
print(odd*even)

Solution (Python):
k=int(input())
if (k%2==1)and k<=100:
    a=k//2
    b=k//2+1
elif (k%2==0)and k<=100:
    a=k//2
    b=k//2
print(a*b)

Solution (Python):
k = int(input())
s = (k + 1) // 2
print(s * (k - s))

Solution (Python):
k=int(input())
if (k%2==1)and k<=100:
    a=k//2
    b=k//2+1
elif (k%2==0)and k<=100:
    a=k//2
    b=k//2
print(a*b)

Solution (Python):
a = int(input())
even, odd = 0, 0

for i in range(a):
    if i % 2 == 0: even = even + 1
    else: odd = odd + 1

print(even * odd)

Solution (Python):
a=int(input())
w=int((a/2)*(a/2))
z=int(a/2)*int((a/2)+1)
if a%2==0:
    print(w)
else:
    print(z)

Solution (Python):
a=int(input())
w=int((a/2)*(a/2))
z=int(a/2)*int((a/2)+1)
if a%2==0:
    print(w)
else:
    print(z)

Solution (Python):
k=int(input())
even=[]
odd=[]
for i in range (1,k+1,1):
    if i%2==0:
        even.append(i)
    else:
        odd.append(i)
result=[(x,y) for x in even for y in odd]
print(len(result))

Solution (Python):
n=int(input())
even=[]
odd=[]
for i in range (1,n+1,1):
    if i%2==0:
        even.append(i)
    else:
        odd.append(i)
result=[(x,y) for x in even for y in odd]
print(len(result))

Solution (Python):
a=int(input())
even=[]
odd=[]
for i in range (1,a+1,1):
    if i%2==0:
        even.append(i)
    else:
        odd.append(i)
result=[(x,y) for x in even for y in odd]
print(len(result))

Solution (Python):
import sys
from fractions import gcd


def main():
    n = int(input())
    print((n // 2) * ((n + 1) // 2))

if __name__ == '__main__':
    main()

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


even = n // 2

odd = n - even

print(even * odd)

Solution (Python):
k = int(input())
m = int(k / 2)

if k % 2 == 0:
    print(m * m)
else:
    print(m * (m + 1))

Solution (Python):
k=int(input())
sum=0
k-=1
while k>0:
    sum+=k
    k-=2
print(sum)

Solution (Python):
x = int(input())
print((x//2) * ((x+1)//2))

Solution (Python):
n=int(input())
if n%2==0:print(int(n/2)**2)
else:print(int(n/2)*(int(n/2)+1))

Solution (Python):
K = int(input())
x = 0
for i in range (0,K,1):
    if i % 2 == 0:
        x +=1
sum = x * (K-x)
print(sum)

Solution (Python):
k=int(input())
if k%2 ==0 :
    print ( int(k/2)*int(k/2) )
else :
    print ( (1+(k//2))*(k//2))

Solution (Python):
s= int(input())
if s%2==0:
    print(int((s//2)**2))
else:
    print(int((s//2)*(s//2+1)))

Solution (Python):
s=int(input())
if s%2==0:
    print(int((s//2)**2))
else:
    print(int((s//2)*(s//2+1)))

Solution (Python):
K = int(input())
if K % 2 == 0:
    ans = K*K//4
if K % 2 == 1:
    ans = ((K-1)//2)*((K-1)//2+1)

print(ans)

Solution (Python):
n = int(input())
ne = n//2
no = n//2 + (1 if n%2 == 1 else 0)
print(ne*no)

Solution (Python):
n=int(input());
print(((n+1)//2)*(n//2))

Solution (Python):
K = int(input())
if K % 2 == 0:
	print(int((K ** 2) / 4))
else:
	print(int((K + 1) * (K - 1) / 4))

Solution (Python):
k=int(input())
if k%2==0:
    print(int((k//2)**2))
else:
    print(int((k**2-1)//4))

Solution (Python):
k=int(input())
if k%2==0:
    print(int((k//2)**2))
else:
    print(int((k**2-1)//4))

Solution (Python):
from math import*
K = int(input())
print(ceil(K/2)*floor(K/2))

Solution (Python):
K = int(input())
print((K//2)**2 if K%2==0 else ((K//2+1)*(K-1))//2)

Solution (Python):
x=int(input())
if x%2==0:
    print((x//2)**2)
else:
    print((x//2)*((x//2)+1))

Solution (Python):
k=int(input())
numofways=0

if k%2==0:
    n=k//2
    numofways=n*n

elif k%2==1:
        n=int(k//2)
        m=n+1
        numofways=n*m

print (numofways)

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

if a % 2 == 0:
    print((a//2)**2)
else:
    print((a//2)*(a//2+1))

Solution (Python):
K=int(input())
l=0
for i in range(1,K+1):
    for z in range(i,K+1):
        if (i%2==0 and z%2==1) or (i%2==1 and z%2==0):
            l+=1
print(l)

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

if a % 2 == 0:
    print((a//2)**2)
else:
    print((a//2)*(a//2+1))

Solution (Python):
x=int(input())
if x%2==0:
    print((x//2)**2)
else:
    print((x//2)*((x//2)+1))

Solution (Python):
x=int(input())
if x%2==0:
    print((x//2)**2)
else:
    print((x//2)*((x//2)+1))

Solution (Python):
n=int(input())
mid=(n+1)//2
if(n%2==0):
    count=mid*mid
else:
    count=  mid*(mid-1)
print(count)

Solution (Python):
x=int(input())
z=0
if x<2:
    print(0)
for i in range(2,x+1,2):
    for j in range(1,x+1,2):
        z+=1
print(z)

Solution (Python):
K=int(input())
i=K//2
if (K%2==0):
    print(i**2)
else:
    print((i**2)+i)

Solution (Python):


k  = int( input())

if (k%2)==0:
  print(int((k/2)**2))
else:
  print(int((k//2)*((k//2)+1)))

Solution (Python):
K=int(input())
a=[]
for i in range(1,K+1):
    a.append(i)

counter=0
if K>=2 and K<=100 :
    for x in range(len(a)):
        for j in range(x+1,len(a)):
            if a[x]&1==0 and a[j]&1==1 or a[x]&1==1 and a[j]&1==0:
                a[x]*a[j]%2==0
                if a[x]*a[j]%2==0:
                    counter+=1
            

    print(counter)

Solution (Python):
k=int(input())
if k%2==0:
    print((k//2)**2)
else:
    print((k//2)*((k//2)+1))

Solution (Python):
k=int(input())
if (k%2)==1 and k<=100:
    a=k//2
    b=k//2+1
elif (k%2)==0 and k<=100:
    a=k//2
    b=k//2
print(a*b)

Solution (Python):
m=int(input())
k=(m/2)**2
if m%2==0:
    print(int(k))
else:
    k = k - 0.25
    print(int(k))

Solution (Python):
k=int(input())
if k%2==0:
    print((k//2)**2)
else:
    print((k//2)*((k//2)+1))

Solution (Python):
k = int(input())
while k < 2 or k > 100:
    k = int(input())

evenNum = []
oddNum = []

for o in range(1, k+1, 2):
    oddNum.append(o)

for e in range(2, k+1, 2):
    evenNum.append(e)

ways = len(evenNum) * len(oddNum)
print(ways)

Solution (Python):
n=input()
O=0
E=0
for i in range (0,int(n)):
    if i%2==0 :
        E+=1
    else:
        O+=1
print (O*E)

Solution (Python):
k = input()
k = int(k)
even = 0
odd = 0
if k >= 2 and k <= 100 :
    for i in range(1, k+1) :
        if i % 2 == 0 :
            even += 1
        else :
            odd += 1

print (even*odd)

Solution (Python):
k= int(input())
if k% 2 == 0:
    print(int((k/2)**2))

elif k%2 ==1:

    print((k//2)* (k-k//2))

Solution (Python):
a=int(input())
print(int(a*a/2/2))

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

odd = k//2 + bool(k%2)
even = k//2

print(odd*even)

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

even = 0
odd = 0

for i in range(1, K + 1):
    if i % 2 == 0:
        even += 1
    else:
        odd += 1

print(even * odd)

Solution (Python):
k=int(input())
count=0
if k>= 2:
    for i in range(2,k+1):
        for j in range(1,k+1):
             if i%2==0 and j%2!=0:
                count+=1
    print(count)

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

if K % 2 == 0:
    print(((K // 2) ** 2))
else:
    print(((K // 2) * ((K // 2) + 1)))

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

print((K//2) * ((K+1)//2))

Solution (Python):
k = int(input())
n = k // 2
m = k - n
print(int(n*m))

Solution (Python):
import math
K = int(input())


if K % 2 == 0:
    print(int(pow(K/2,2)))
else:
    print(int(((K-1)/2) * ((K+1)/2)))

Solution (Python):
import math
K = int(input())


if K % 2 == 0:
    print(int(pow(K/2,2)))
else:
    print(int(((K-1)/2) * ((K+1)/2)))

Solution (Python):
k=int(input())
Even=0
Odd=0
for i in range (k) :
    if i%2==0:
        Even+=1
    else :
        Odd+=1

print(Even*Odd)

Solution (Python):
k = int(input())
if 2<=k<=100:
 n = k // 2
 m = k - n
print(int(n*m))

Solution (Python):

k = int(input())
print((k // 2) * (k // 2 + k % 2))

Solution (Python):
K = int(raw_input())
print K / 2 * (K / 2 + K % 2)

Solution (Python):
k = int(input())
ressult = (k//2) * (k//2 + k%2)
print(ressult)

Solution (Python):
k=int(input())
if k%2==0:
    ki=int(k/2)
    gu=int(k/2)
else:
    ki=int(k/2)+1
    gu=int(k/2)
print(ki*gu)

Solution (Python):
k=int(input())
count=0
for i in range (2,k+1,1):
    for j in range (k+1):
        if i%2==0 and j%2==1:
            count+=1

print(count)

Solution (Python):
import math

n = int( input())

print( math.ceil(n/2) * math.floor(n/2))

Solution (Python):
k = int(input())
x = [i for i in range(1, k+1) if i & 1 == 0]
y = [i for i in range(1, k+1) if i & 1 == 1]
print(len(x)*len(y))

Solution (Python):


if __name__ == "__main__":
    K = int(input())
    if K % 2 == 0:
        print(int(K/2)**2)
    else:
        print(int(K/2)*int(K/2+1))

Solution (Python):
k =int(input())
ans = 0
for i in range(k+1):
	t = i // 2
	ans += t
print(ans)

Solution (Python):
k = int(input())
if k % 2 == 0:
    print((k // 2)**2)
else:
    print((k - (k // 2)) * (k // 2))

Solution (Python):
n=int(input())
e=int(n/2)
if n%2:
	o=int(n/2+1)
else:
	o=int(n/2)
	
print (o*e)

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

odd = []
even = []
for i in range(1, k + 1):
    if i % 2 == 0:
        even.append(i)
    else:
        odd.append(i)

ans = len(even) * len(odd)
print(ans)

Solution (Python):
x = int(input())
a = x//2
b = x - a
print(a*b)

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

odd=0
even=0

for i in range(K):
	if i%2==0:
		even+=1
	else:
		odd+=1

print(even*odd)

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

odd = 0
even = 0

for i in range(K):
    if i % 2 == 0:
        even += 1
    else:
        odd += 1

print(even * odd)

Solution (Python):
n = int(input())
if n&1==0:
    print((n//2)**2)
else:
    print((n//2)*(n//2+1))

Solution (Python):
def solve(k):
    p = k / 2
    return (k - p) * p

assert solve(3) == 2
assert solve(6) == 9
assert solve(11) == 30
assert solve(50) == 625
print solve(input())

Solution (Python):
import math
x=int(input())

print(math.ceil(x/2)*(x//2))

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

list = [x for x in range(1,K+1)]

list_odd = list[1::2]
list_even = list[0::2]

cnt = 0

for i in list_odd:
    for j in list_even:
        cnt += 1

print(cnt)

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

a = k//2
b = (k+1)//2

print(a*b)

Solution (Python):

K = int(input())
print((K//2)*(K//2+1) if K%2!=0 else (K//2)**2)

Solution (Python):
n=int(input())
m=n//2
print((n-m)*m)

Solution (Python):
from itertools import combinations

K = int(input())
num = list(combinations(list(range(1, K+1)), 2))
ans = list(filter(lambda x: sum(x)%2 != 0, num))
print(len(ans))

Solution (Python):
num = int(input())
even = 0
odd = 0
for n in range(num):
    if n % 2 == 0:
        even += 1
    else:
        odd += 1

print(even*odd)

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

even = n // 2
odd = n - even

answer = odd * even
print(answer)

Solution (Python):
n = int(input())
l = range(1, n + 1)
gu = l[1::2]
ki = l[::2]
print(len(gu) * len(ki))

Solution (Python):
K = int(input())
print((K//2) * ((K+1)//2))

Solution (Python):
K=int(input());print(K//2*int(K/2+0.5))

Solution (Python):
k=int(input())
print((k//2)*(-(-k//2)))

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

even = []
odd  = []
for i in range(K):
    if i % 2 == 0:
        even.append(i)
    else:
        odd.append(i)
        
print(len(even) * len(odd))

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

a = K // 2
b = K - a

print(a * b)

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

if k % 2 == 0:
     print((k//2)**2)
else:
     print((k//2)*((k//2)+1))

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

if k % 2 == 0:
     print((k//2)**2)
else:
     print((k//2)*((k//2)+1))

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

if k % 2 == 0:
    print((k//2)**2)
else:
    print((k//2)*((k//2)+1))

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

if k % 2 == 0:
    print((k//2)**2)
else:
    print((k//2)*((k//2)+1))

Solution (Python):
k = int(input())
if k%2 == 0:
    print((k//2)*(k//2))
else:
    print((k//2)*(k//2+1))

Solution (Python):


n = int(input())

a = n//2

print(a*(n-a))

Solution (Python):
k = int(input())
ans = (k//2)**2 if k%2 == 0 else k//2 * (k//2+1)
print(ans)

Solution (Python):
k = int(input())
if k % 2 == 0:
    print((k//2)**2)
else:
    print((k//2) * (k//2+1))

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

print((n//2)*((n+1)//2))

Solution (Python):
n=int(input())
a=0
if(n%2==0):
    print(n//2*n//2)
else:
    print((n+1)//2*(n-1)//2)

Solution (Python):
import math
n = int(input())
print(int(math.floor(n/2) * math.ceil(n/2)))

Solution (Python):
K = int(input())
even = 0
odd = 0

for i in range(1,K+1):
	if i%2 == 0:
		even += 1
	else:
		odd += 1

print(even*odd)

Solution (Python):
k = int(input())
print(( k // 2 ) * ( k - k // 2 ))

Solution (Python):
k = int(input())
print(int(k*k/4))

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

ans = 0

if k % 2 == 0:
    ans = (k // 2) * (k // 2)

else:
    ans = (k // 2) * (k // 2 + 1)

print(ans)

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

for i in range(2, K+1, 2):
    for j in range(1, K+1, 2):
        count += 1

print(count)

Solution (Python):
k = input()
if (k%2==0):
	print((k/2)*(k/2))
else:
	print((k/2)*(k/2 + 1))

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

if(K % 2 == 0):
    check = K / 2
    print(int(check * check))
else:
    print(int(((K+1)/2)*((K-1)/2)))

Solution (Python):
k = int(input())
even = k//2
odd = k - even
print(even*odd)

Solution (Python):
k = int(input())
print(int(k/2)*int((k+1)/2))

Solution (Python):
n =int(input())
print(len([i for i in range(1,n+1) if i % 2 == 1])*len([i for i in range(1,n+1) if i % 2 == 0]))

Solution (Python):
def answer(in0):
    n = int(in0)
    base = int(n / 2)
    odd = base + ((n%2) != 0)
    even = base

    return odd * even

print(answer(input()))

Solution (Python):
k = int(input())
n = k // 2
m = (k+1) // 2
print(n*m)

Solution (Python):
K = int(input())
ans = 0


if K % 2 == 0:
    ans = (K / 2)**2
elif K % 2 == 1:
    ans = (int((K / 2))) * (int((K / 2)) + 1)

print(int(ans))

Solution (Python):
K = int(input())
ans = 0


if K % 2 == 0:
    ans = (K / 2)**2
elif K % 2 == 1:
    ans = (int((K / 2))) * (int((K / 2)) + 1)

print(int(ans))

Solution (Python):
n = int(input())
print(int((n/2))*int((n+1)/2))

Solution (Python):
k = int(input())
if k%2 == 0:
  print(int((k/2)**2))
else:
  print((k//2)*(k//2+1))

Solution (Python):
x = int(input())
y = x // 2
print(y*(x-y))

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

if k % 2 == 0:
    print((k//2)**2)
else:
    print((k//2)*((k//2)+1))

Solution (Python):
n=int(input())
m=n//2
print((n-m)*m)

Solution (Python):
def solve(string):
    k = int(string)
    return str((k // 2) * ((k + 1) // 2))


if __name__ == '__main__':
    print(solve(input()))

Solution (Python):
K = int(input())
if K % 2 == 0:
    a = (K / 2) ** 2
    print(int(a))
else:
    b = (K / 2 + 0.5) * (K / 2 - 0.5)
    print(int(b))

Solution (Python):
k = int(input())
if k%2 == 0:
    a = (k/2)**2
    print(int(a))
else:
    a = ((k-1)/2)*((k-1)/2 + 1)
    print(int(a))

Solution (Python):
K = int(input())
if K % 2 == 0:
    res = (K/2)**2
else:
    res = ((K-1)/2)*((K-1)/2 + 1)
print(int(res))

Solution (Python):
print((lambda a:(a//2)*((a+1)//2))(int(input())))

Solution (Python):
k = int(input())
cnt = 0

for i in range(1,k+1):
	for j in range(1,k+1):
		if i%2==0 and j%2!=0:
			cnt += 1

print(cnt)

Solution (Python):
K=int(input())
c_gu=0
c_ki=0
if (K%2==0):
    c_gu=int(K/2)
    c_ki=int(K/2)
else:
    c_gu=int(K/2)+1
    c_ki=int(K/2)
print(c_gu*c_ki)

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

if n %2 == 1:
    print(int((n**2-1)/4))
else:
    print(int((n**2)/4))

Solution (Python):
try:

    
    k = int(input()) 

    
    e = int(k / 2)
    o = e if k % 2 == 0 else e + 1

    
    print(e * o)

except EOFError:
    pass

Solution (Python):
K = int(input())
print(K//2 * (K-K//2))

Solution (Python):
k = int(input())
even = k // 2
odd = even

if k % 2 == 1:
    odd = even + 1

print(odd * even)

Solution (Python):
import sys


def solve(K) : 
    x = K//2
    if K%2==0 :
        return x**2
    else :
        y = x+1
        return x*y

def readQuestion():
    line = sys.stdin.readline().rstrip()
    return int(line)

def main():
    n = readQuestion()
    answer = solve(n)
    print(answer)
    
if __name__ == '__main__':
    main()

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

if k % 2 == 0:
  print((k//2)**2)
else:
  print((k//2) * ((k//2)+1))

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

even=0
odd=0
for i in range(1,K+1):
    if(i%2==0):
        even+=1
    else:
        odd+=1
print(even*odd)

Solution (Python):
K = int(input())
even = K//2
odd = K-even
print(odd*even)

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

if N%2==0:
    a=(N//2)**2

else:
    a=(N//2)*(N//2+1)


print(a)

Solution (Python):
K = int(input())
a = int(K/2)
b = int((K+1)/2)

print (a*b)

Solution (Python):
from math import floor
n = int(input())
ans = 0
if n%2==0:
    ans = (n/2)**2
else:
    ans = (n-1)*(n+1)/4
print(floor(ans))

Solution (Python):
k=int(input())
odd_cnt=0
even_cnt=0
for i in range(1,k+1):
    if i%2==0:
        even_cnt+=1
    else:
        odd_cnt+=1
print(even_cnt*odd_cnt)

Solution (Python):
k=int(input())
a=k//2
print(a*a) if k%2==0 else print(a*(a+1))

Solution (Python):
n = int(input())
a = 0
if n%2 == 0:
  a = (n/2)**2
else:
  a = (n**2-1)/4
print(int(a))

Solution (Python):
K = int(input())
if K%2 == 0:
    odd_number = K // 2
elif K%2 == 1:    
    odd_number = K // 2 + 1
even_number = K // 2 

print(odd_number*even_number)

Solution (Python):
n = int(input())
even = n // 2
if n % 2 == 0:
    odd = n // 2
else:
    odd = n // 2 + 1
print(even * odd)

Solution (Python):
n = int(raw_input())
e = n / 2
print e * (n-e)

Solution (Python):
K = int(input())
ans = (K//2) * ((K+1)//2)
print(ans)

Solution (Python):
k = int(input())
x = k // 2
print(x * (k-x))

Solution (Python):



def main():
    k = int(input())
    print((k // 2) * (k - k // 2))


if __name__ == '__main__':
    main()

Solution (Python):
K=int(input())
a=int(K/2)
b=int((K+1)/2)
print(int(a*b))

Solution (Python):
K = int(input())
p = K//2
print(p*(K-p))

Solution (Python):
n = int(input())
a = n // 2
b = n // 2 + n % 2
print(a*b)

Solution (Python):


a = int(input())

odd = a /2
even = a / 2

print( int(odd * even))

Solution (Python):
K = int(input())
list = [i for i in range(1, K + 1)]
odd = list[1::2]
even = list[0::2]

cnt = 0

for i in odd:
    for j in even:
        cnt += 1

print(cnt)

Solution (Python):
from math import floor, ceil
K = int(input())
ans = floor(K / 2) * ceil(K / 2)
print(ans)

Solution (Python):
def solve(K):
    ans = ((K + 1) // 2) * (K // 2)
    print(ans)

K = int(input())
solve(K)

Solution (Python):
"""
A - Pair
1 以上 K 以下の正の整数から、偶数と奇数ひとつずつの組を選ぶ方法の個数を求めてください。なお、選ぶ順番は考慮しません。

K=６のとき、
選ぶ組の距離は、１，３，５となる
これを列挙すればよいはず
"""

K = int(input())

cnt = 0
for start in range(1, K):
    for dist in range(1, K, 2):
        if (start + dist) <= K:
            cnt += 1
        else:
            break

print(cnt)

Solution (Python):

K = int(input())
if K % 2 == 0:
    ans = K * K / 4
else:
    ans = (( K - 1) / 2) **2 + (K-1)/2

print(int(ans))

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

print(K//2 * ((K+1)//2))

Solution (Python):
a = int(input())
b = a // 2
c = a - b
print(c*b)

Solution (Python):
n = int(input())
if n % 2 == 0:
  print(n//2 * n//2)
else:
  print(n//2 * (n//2+1))

Solution (Python):
K = input()

gusu = int(int(K) / 2)
kisu = int((int(K)+1) / 2)

print(int(kisu * gusu))

Solution (Python):
k = int(input())
if k % 2 == 0:
    n = int((k/2) * (k/2))
else:
    n = int((k-1)/2 * ((k-1)/2 + 1))
print(n)

Solution (Python):
K = int(input())
if K % 2 == 0:
    print(int((K/2)**2))
else:
    print(int((K-1)/2*((K-1)/2+1)))

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

even = K // 2

if (K%2):
    odd = K // 2 + 1
else:
    odd = K // 2

ans = even * odd
print(ans)

Solution (Python):
K = int(input())
if K % 2 == 0:
    print(int((K/2)**2))
else:
    print(int((K//2+1)*(K//2)))

Solution (Python):
import math
N = int(input())

even = N // 2
odd = math.ceil(N/2)
print(even*odd)

Solution (Python):
k = int(input())
if k % 2 == 0:
    print( (k // 2) * (k // 2 ))
else:
    print( ((k - 1) // 2 + 1) * ((k - 1) // 2) )

Solution (Python):
A = int(input())
print(A//2*int(A/2+0.5))

Solution (Python):
import math
K = int(input())

if K % 2 == 0:
    S = (K//2) ** 2
    print(S)

else: 
    S = math.floor(K/2) * math.ceil(K/2)
    print(S)

Solution (Python):
K = int(input())
if (K%2==0):
    print((K//2)**2)
else:
    print((K//2)*(K-K//2))

Solution (Python):
K = int(input())
print((K//2)*(K-K//2))

Solution (Python):


a = int(input())

odd = a /2
even = a / 2

print( int(odd * even))

Solution (Python):
import numpy as np
import math

K = int(input())

ki = math.floor(K / 2)
gu = math.ceil(K / 2)

print(ki * gu)

Solution (Python):
import math

k = int(input())

if k%2:
    print(math.floor(k/2)*math.ceil(k/2))
else:
    print(int((k/2)**2))

Solution (Python):

import sys

def main():
    k = int(input())
    ev = k // 2

    if k % 2 == 1:
        od = ev + 1
    else:
        od = ev

    print(ev * od)

if __name__ == '__main__':
    main()

Solution (Python):
k = int(input())
print((k // 2) * (k - (k // 2)))

Solution (Python):
k = int(input())
print(k//2*(k-k//2))

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

if k % 2 is 0:
  print(int((k/2)**2))
else:
 print(int(((k-1)/2)*(((k-1)/2)+1)))

Solution (Python):
a=int(input())
if a%2==0:print(int(a/2)**2)
else:print((a//2)*((a//2)+1))

Solution (Python):
k=int(input())
hk=k//2
print(hk*(k-hk))

Solution (Python):
K = int(input().strip())
num1 = K // 2
num2 = K - num1
print(num1 * num2)

Solution (Python):
def solution(k):
    return (k >> 1) * ((k + 1) >> 1)

def main():
    k = int(raw_input().strip())
    print solution(k)

if __name__ == '__main__':
    main()

Solution (Python):
def main():
    K = int(input())
    odd = (K + 1) // 2
    even = K // 2
    print(odd * even)

if __name__ == '__main__':
    main()

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

ans = set()
for i1 in range(1,k+1):
  for i2 in range(1,k+1):
    if i1%2 == 0 and i2%2 == 1:
      ans.add( (i1, i2) )      
print(len(ans))

Solution (Python):
x = input()

print((int(x) // 2) * ((int(x) + 1) // 2))

Solution (Python):
K = int(input())
a = K // 2
b = (K + 1) // 2
print(a * b)

Solution (Python):
n = input()
print (n + 1) / 2 * (n / 2)

Solution (Python):
k=int(input())
print(k//2*((k+1)//2))

Solution (Python):
x = [i for i in range(1,int(input()) + 1)]
print(len(x[0::2])*len(x[1::2]))

Solution (Python):
k=int(input())
even,odd=0,0
if 2<=k<=100:
	for i in range(1,k+1):
		if i%2==0:
			even +=1
		else:
			odd +=1
print(even*odd)

Solution (Python):
k=int(input())
even,odd=0,0
if 2<=k<=100:
	for i in range(1,k+1):
		if i%2==0:
			even +=1
		else:
			odd +=1
print(even*odd)

Solution (Python):
k=int(input())
even,odd=0,0
if 2<=k<=100:
	for i in range(1,k+1):
		if i%2==0:
			even +=1
		else:
			odd +=1
print(even*odd)

Solution (Python):
K = int(input())
even = K // 2
odd = (K + 1) // 2
print(odd * even)

Solution (Python):
K=int(input())
if K%2 == 0:
    M=K*K/4
    print(int(M))
else:
    M=(K-1)*(K+1)/4
    print(int(M))

Solution (Python):
K=int(input())
even=int(K/2)
print(even*(K-even))

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

if n%2==0:
    print(n*n//4)
else:
    print((n-1)//2*(n+1)//2)

Solution (Python):
if __name__ == '__main__':
    K = int(input())
    odds = int((K+1)/2)
    even = int(K/2)
    print(odds*even)

Solution (Python):
k = int(input())
n,m = (k+1)//2 , k//2
print(n*m)

Solution (Python):
import sys
a=int(input())
b=a/2
c=b*(a-b)
print(int(c))

Solution (Python):
K = int(input())
if K & 1:
  print((K//2) * ((K+1)//2))
else:
  print((K//2) * (K//2))

Solution (Python):
K = int(input())
c1 = 0
c2 = 0
for i in range(K):
    if i % 2 == 0:
        c1 +=1
    else :
        c2 +=1
print(c1*c2)

Solution (Python):
K = int( input())
if K%2 == 0:
    print(K//2*K//2)
else:
    print(K//2*(K//2 + 1))

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

num=K//2

print(num*(K-num))

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

print ( "%d" % ( (k+1)//2 * (k//2) ) )

Solution (Python):
k = int(input())
if k%2 == 0:
  print(int(k*k/4))
else:
  print(int((k*k-1)/4))

Solution (Python):
K = int(input())
even = K//2
odd = K - even

print(even*odd)

Solution (Python):
n=int(input())
a=n//2
print(a*(a+n%2))

Solution (Python):
iK = int(input())
if iK % 2 == 0:
  iN = int(iK / 2)
  print(iN * iN)
else :
  iN = int((iK - 1)/2)
  print(iN * (iN + 1))

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

if k%2==0:
    ans = k/2*k/2
else:
    ans = ((k//2)+1)*(k//2)


ans = int(ans)
print(ans)

Solution (Python):

k = int(input())
print (int(k/2)*int((k+1)/2))

Solution (Python):


k = int(input())

even = int(k/2)

odd = k-even

print(odd*even)

Solution (Python):
k=int(input())
ans=0
if k%2==0:
	ans=k*k/4
else:
  	ans=(k*k-1)/4
print(int(ans))

Solution (Python):
k = int(input())
even = k//2
odd = (k+1)//2
a = even * odd
print(a)