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

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

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

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

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

if __name__ == '__main__':
    solve()

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

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

Solution (Python):


k = int(input())

print((k // 2) * ((k // 2) + (k % 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())

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

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

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

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

Solution (Python):
K = int(input())
res = 0
for i in range(1,K+1):
  if i % 2 == 0:
    for j in range(i+1,K+1):
      if j%2 !=0:
        res+=1
  else:
    for j in range(i+1,K+1):
      if j%2 ==0:
        res+=1
        
print(res)

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

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

Solution (Python):
def main():
    from builtins import int, map, list, print
    import sys
    sys.setrecursionlimit(10 ** 6)

    input = (lambda: (sys.stdin.readline()).rstrip())
    input_list = (lambda: input().split())
    input_number = (lambda: int(input()))
    input_number_list = (lambda: list(map(int, input_list())))

    K = input_number()
    print(-(-K // 2) * (K // 2))


if __name__ == '__main__':
    main()

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

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

if k % 2 == 1:
    o = n + 1
    print(o*n)

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

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

ki = 0
for j in range(1,K+1):
    if j % 2 ==1:
        ki+=1

print(gu*ki)

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

Solution (Python):
import sys
import math
import itertools
import bisect
from copy import copy
from collections import deque,Counter
from decimal import Decimal
def s(): return input()
def i(): return int(input())
def S(): return input().split()
def I(): return map(int,input().split())
def L(): return list(input().split())
def l(): return list(map(int,input().split()))
def lcm(a,b): return a*b//math.gcd(a,b)
sys.setrecursionlimit(10 ** 9)
mod = 10**9+7

K = i()
print(K//2*(K-K//2))

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

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

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

Solution (Python):
def ip():return int(input())

k=ip()
print((k+1)//2*(k//2))

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())

od = []
ev = []

for i in range(1,k+1):
    if i % 2 == 0:
        ev.append(i)
    else:
        od.append(i)

print(len(od)*len(ev))

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

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

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

Solution (Python):
def i():
	return int(input())
def i2():
	return map(int,input().split())
def s():
	return str(input())
def l():
	return list(input())
def intl():
	return list(int(k) for k in input().split())

k = i()
ans = 0
ls = list(int(k) for k in range(1,k+1))
for i in range(k):
	ans += ls[i]//2
print(ans)

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

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

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

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

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

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

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

Solution (Python):
N = int(input())
print((N >> 1) * ((N >> 1) + (N & 1)))

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

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

for i in range(k):
    if i % 2 == 0:
        for j in range(k):
            if j % 2 != 0:
                count += 1
print(count)

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

Solution (Python):
import sys
input=sys.stdin.readline
k=int(input())
e=k//2
if k%2==0:
    o=e
else:
    o=e+1
print(o*e)

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

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

r = k % 2
x = k // 2
y = (k + 1) // 2
z = (k - 1) // 2

if r == 0:
  print(x ** 2)
else:
  print(y * z)

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())

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

Solution (Python):
k = int(input())
n = k//2
a = n*(n+1)//2
x = (k-1)%2
print(a*2 - x*n)

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

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

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

p = k // 2

if k % 2 == 0:
    print(p * p)
elif k % 2 > 0:
    print(p*(p+1))

Solution (Python):
def actual(k):
    n_even = k // 2
    n_odd = (k + 1) // 2

    return n_even * n_odd

k = int(input())
print(actual(k))

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

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

if k % 2 == 0:
    num = k ** 2 /4
else:
    base = (k-1) / 2
    num = base * (base + 1)

print(int(num))

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

if k % 2 == 0:
    num = k * k /4
else:
    base = (k-1) / 2
    num = base * (base + 1)

print(int(num))

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

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

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

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

count = 0
for i in range(1, K+1):
    for j in range(i+1, K+1, 2):
        count += 1
print(count)

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

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

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

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

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

Solution (Python):


K = int(input())

even = K//2
odd = (K+1)//2

print(even*odd)

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

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

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

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

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

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

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

a = (k + 1) // 2

b = k // 2


print(a * b)

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

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


def main():
    k = int(input())
    if k % 2 == 0: print((k // 2) ** 2)
    if k % 2 != 0: print(((k - 1) // 2) * (k + 1) // 2)
    

if __name__ == "__main__":
    main()

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

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

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

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

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

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

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

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

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 = int(N/2)

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

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

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

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

Solution (Python):

k=int(input())

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

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

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

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())
print(n//2*(n+1)//2) if n%2 else print((n//2)**2)

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

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

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

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

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

    if k % 2:
        res = (k // 2) * (k - k // 2)
    else:
        res = (k // 2) ** 2

    print(res)

if __name__ == '__main__':
    main()

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

Solution (Python):
from itertools import combinations


K = int(input())


cnt = len(
    [
        1
        for c in list(combinations(list(range(1, K + 1)), 2))
        if (c[0] + c[1]) % 2 == 1
    ]
)

print(cnt)

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

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

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

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

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

print(ans)

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

even = k%2 == 0
ans = k >> 1

if even:
    ans **= 2
else:
    ans *= (ans+1)

print(ans)

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

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

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

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

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

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

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

print(n // 2 * (n - n // 2))

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

for i1 in range(1,K+1):
  for i2 in range(i1+1, K+1):
    if i1%2 != 0 and i2%2 == 0:
      cnt = cnt+1
    elif i1%2 ==0 and i2%2 != 0:
      cnt = cnt+1
      
print(cnt)

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

print(n // 2 * (n - n // 2))

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

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

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

Solution (Python):
import itertools

N = int(input())
odd = N // 2 + N % 2
even = N // 2

print(odd * even)

Solution (Python):






def main():
    k = int(input())

    return ((k + (k % 2)) // 2) * (k // 2)


print(main())

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

e = k // 2
o = k - e
ans = e * o
print(ans)

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

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

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

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

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

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

print(ans)

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

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

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

Solution (Python):
from collections import defaultdict, deque, Counter
from heapq import heappush, heappop, heapify
from itertools import permutations, accumulate, combinations, combinations_with_replacement
from math import sqrt, ceil, floor, factorial
from bisect import bisect_left, bisect_right, insort_left, insort_right
from copy import deepcopy
from operator import itemgetter
from functools import reduce
from fractions import gcd
import sys
def input(): return sys.stdin.readline().rstrip()
def I(): return int(input())
def Is(): return map(int, input().split())
def LI(): return list(map(int, input().split()))
def TI(): return tuple(map(int, input().split()))
def IR(n): return [I() for _ in range(n)]
def LIR(n): return [LI() for _ in range(n)]
def TIR(n): return [TI() for _ in range(n)]
def S(): return input()
def Ss(): return input().split()
def LS(): return list(input())
def SR(n): return [S() for _ in range(n)]
def SsR(n): return [Ss() for _ in range(n)]
def LSR(n): return [LS() for _ in range(n)]
sys.setrecursionlimit(10**6)
MOD = 10**9+7
INF = 10**18


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

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

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

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

Solution (Python):
def cmb(n):
    return (n * (n - 1)) / 2

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

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

Solution (Python):
inf = 10 ** 15
mod = 10 ** 9 + 7
k = int(input())
if k % 2 == 0:
    print((k//2)*(k//2))
else:
    print((k//2+1)*(k//2))

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

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

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



print( N ** 2 // 4)

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

Solution (Python):
import sys
import math
import bisect

def main():
    n = int(input())
    ans = 0
    for i in range(1, n + 1):
        for j in range(1, n + 1):
            if i % 2 == 0 and j % 2 == 1:
                ans += 1
    print(ans)

if __name__ == "__main__":
    main()

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

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

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

Solution (Python):
print(int(input())**2>>2)

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

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

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

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

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

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

Solution (Python):

import sys

sr = lambda: sys.stdin.readline().rstrip()
ir = lambda: int(sr())
lr = lambda: list(map(int, sr().split()))

K = ir()
even = K // 2
odd = (K+1) // 2
answer = even * odd
print(answer)

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

Solution (Python):
import sys

input = sys.stdin.readline


def main():
    K = int(input())

    n_odd = 0
    n_even = 0
    for i in range(1, K + 1):
        if i % 2 == 0:
            n_even += 1
        else:
            n_odd += 1
    ans = n_odd * n_even

    print(ans)


if __name__ == "__main__":
    main()

Solution (Python):
def ABC_108_A():
    K = int(input())

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

if __name__ == '__main__':

    ABC_108_A()

Solution (Python):


import sys






















def main():
    mod = 1000000007                
    inf = float('inf')              
    
    sys.setrecursionlimit(10**6)    
    def input(): return sys.stdin.readline().rstrip()
    def ii():    return int(input())
    def mi():    return map(int, input().split())
    def mi_0():  return map(lambda x: int(x)-1, input().split())
    def lmi():   return list(map(int, input().split()))
    def lmi_0(): return list(map(lambda x: int(x)-1, input().split()))
    def li():    return list(input())
    
    
    n = ii()
    if n % 2 == 0:
        print((n // 2) ** 2)
    else:
        print((n // 2) * (n // 2 + 1))


if __name__ == "__main__":
    main()

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

Solution (Python):
import itertools
K=list(itertools.combinations(range(1,int(input())+1),2))
c=0
for i in K:
    if (i[0]%2==0 and i[1]%2==1) or (i[0]%2==1 and i[1]%2==0):
        c+=1
print(c)

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

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

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

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

Solution (Python):
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())
print((K//2)*(K-K//2))

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

Solution (Python):

import sys
import math
from bisect import bisect_left, bisect_right, insort_left, insort_right
from collections import defaultdict, deque, Counter
from copy import deepcopy
from fractions import gcd
from functools import lru_cache, reduce
from heapq import heappop, heappush
from itertools import accumulate, groupby, product, permutations, combinations, combinations_with_replacement
from math import ceil, floor, factorial, log, sqrt, sin, cos
from operator import itemgetter
sys.setrecursionlimit(10**7)
rs = lambda: sys.stdin.readline().rstrip()
ri = lambda: int(rs())
rf = lambda: float(rs())
rs_ = lambda: [_ for _ in rs().split()]
ri_ = lambda: [int(_) for _ in rs().split()]
rf_ = lambda: [float(_) for _ in rs().split()]
INF = float('inf')
MOD = 10 ** 9 + 7
PI = math.pi


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

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

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

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

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//2+k%2))

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

Solution (Python):


def main():
    K = int(input())

    print((K//2)*(-(-K//2)))


main()

Solution (Python):
k=int(input())
print(k**2//4)

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

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

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

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

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

Solution (Python):
k=int(input())
cnt=1
for i in range(3,k+1):
  cnt+=i//2
print(cnt)

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

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

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

Solution (Python):


K = int(input())

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

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

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

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

print(cnt)

Solution (Python):


k = int(input())
odd = k // 2
if k % 2 == 1:
    odd += 1
print(odd * (k-odd))

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

Solution (Python):
MOD = 10 ** 9 + 7
INF = 10 ** 11
import sys
sys.setrecursionlimit(100000000)

def main():
    k = int(input())
    if k%2 == 0:
        print((k//2)*(k//2))
    else:
        print((k//2)*(k//2 + 1))
if __name__ == '__main__':
    main()

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

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

e = k // 2
o = k // 2 + k % 2

print(e*o)

Solution (Python):

import math
n = int(input())
print(int(n/2) * math.ceil(n/2))

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

print(odd_count*(k-odd_count))

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

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

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

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

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

Solution (Python):
import math

k = int(input())
gusu = math.floor(k/2)
kisu = math.ceil(k/2)


def combinations_count(n, r):
   return math.factorial(n) // (math.factorial(n - r) * math.factorial(r))

ans = combinations_count(gusu,1)*combinations_count(kisu,1)
print(ans)

Solution (Python):
import math

k = int(input())

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

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

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

print((K//2) * (K - (K//2)))

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

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

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())

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

print(odd*even)

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

Solution (Python):
x=range(1,int(input())+1)
y=[t for t in x if t%2==0]
z=[t for t in x if t%2==1]
print(len(y)*len(z))

Solution (Python):
x=range(1,int(input())+1)
y=[t for t in x if t%2==0]
z=[t for t in x if t%2==1]
print(len(y)*len(z))

Solution (Python):

import sys


def solve(K: int):
    print((K // 2) * ((K + 1) // 2))


def main():
    def iterate_tokens():
        for line in sys.stdin:
            for word in line.split():
                yield word
    tokens = iterate_tokens()
    K = int(next(tokens))  
    solve(K)


if __name__ == '__main__':
    main()

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

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

a = (k + 1) // 2

if k % 2 == 0:
  print((k // 2) ** 2)
else:
  print(a ** 2 - a)

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

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

print((K//2)*(K - K//2))

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

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

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

Solution (Python):
print(int(input())**2>>2)

Solution (Python):
k = int(input()) + 1
gusu = []
kisu = []
for i in range(1, k):
  if i % 2 == 0:
    gusu.append(i)
  else:
    kisu.append(i)
count = 0
for i in gusu:
  for j in kisu:
    count += 1
print(count)

Solution (Python):


a = int(input())
print(a // 2 * (a - a // 2))

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

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

Solution (Python):
import math
k = int(input())
odd = math.ceil(k/2)
print(odd*(k-odd))

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

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

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

oddNum = int((K + 1) / 2)
evenNum = int(K/2)

print(oddNum * evenNum)

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):
import sys, re
from collections import deque, defaultdict, Counter
from math import ceil, sqrt, hypot, factorial, pi, sin, cos, radians
from itertools import accumulate, permutations, combinations, product, groupby
from operator import itemgetter, mul
from copy import deepcopy
from string import ascii_lowercase, ascii_uppercase, digits
from bisect import bisect, bisect_left
from fractions import gcd
from heapq import heappush, heappop
from functools import reduce
def input(): return sys.stdin.readline().strip()
def INT(): return int(input())
def MAP(): return map(int, input().split())
def LIST(): return list(map(int, input().split()))
def ZIP(n): return zip(*(MAP() for _ in range(n)))
sys.setrecursionlimit(10 ** 9)
INF = float('inf')
mod = 10 ** 9 + 7

K = INT()
print((K-K//2) * (K//2))

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

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

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

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

odd = list(range(1, K+1, 2))
even = list(range(2, K+1, 2))


def combinations_count(n, r):
    return math.factorial(n) // (math.factorial(n - r) * math.factorial(r))


print(combinations_count(len(odd), 1)*combinations_count(len(even), 1))

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

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

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

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

a = int(k//2)
b = int(k-a)

print(a*b)

Solution (Python):
import math
def main():
    K = int(input())
    if K % 2 == 0:
        print(K**2//4)
    else:
        print(math.floor(K//2)*(math.floor(K//2)+1))
if __name__ == "__main__":
    main()

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

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

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

Solution (Python):
k = int(input())
even = [i for i in range(1, k+1) if i%2==0]
odd = [i for i in range(1, k+1) if i%2!=0]
ans_lst = []
for i in even:    
    for j in odd:
        even_odd = []
        even_odd.append(i)
        even_odd.append(j)
        ans_lst.append(even_odd)
print(len(ans_lst))

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

even, odd = 0, 0

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

print(even * odd)

Solution (Python):
def main():
    import sys
    input = sys.stdin.readline
    sys.setrecursionlimit(10**7)
    from collections import Counter, deque
    
    from itertools import combinations, permutations, accumulate, groupby, product
    from bisect import bisect_left,bisect_right
    from heapq import heapify, heappop, heappush
    from math import floor, ceil
    

    
    

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

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

else:
    print( (k//2)*(k//2 + 1) )