chapter 2:)
'''
4016
def idk(x, y, z):
a = 0
if x>y:
a = y
else:
a = x
if a>z:
a = z
k = 0
for i in range(1, a+1):
if x % i == 0 and y % i == 0 and z % i == 0:
k=i
print(k)
a, b, c = input().split()
a = int(a)
b = int(b)
c = int(c)
idk(a, b, c)
4021
def idk(x):
k = 0
for i in range(len(x)):
if x[i] % 2 != 0:
k += x[i]
if k == 0:
k = -1
print(k)
arr = input().split()
for i in range(len(arr)):
arr[i] = int(arr[i])
idk(arr)
4026
def idk(x):
x.sort()
if len(x) % 2 != 0:
print(x[len(x)//2])
else:
w = x[len(x)//2] + x[len(x)//2 + 1]
w = w /2
print(w)
arr = input().split()
for i in range(len(arr)):
arr[i] = int(arr[i])
idk(arr)
4031
def idk(x):
a = []
b = []
a.append(0)
b.append(0)
for i in range(len(x)):
if x[i] % 2 == 0:
a.append(x[i])
a.sort()
n = a[-1]
for i in range(len(x)):
if x[i] % 2 != 0:
b.append(x[i])
b.sort()
m = b[-1]
print(n + m)
arr = input().split()
for i in range(len(arr)):
arr[i] = int(arr[i])
idk(arr)
4051
def idk(x):
d = 0
for i in range(5):
k = x[i][1] - x[i][0]
if k <= 1:
k = 0
else:
k -= 1
if k > 4:
k = 4
d += k
k = d * 10000
if d >= 15:
k = k * 0.95
elif d <= 5:
k = k * 1.05
print(int(k))
n = []
for i in range(5):
arr = input().split()
for j in range(len(arr)):
arr[j] = float(arr[j])
n.append(arr)
idk(n)
4816
def idk(x):
if x >= 300:
a = x / 300
else:
a = 0
if (x % 300) >= 60:
b = (x % 300 )/ 60
else:
b = 0
if (x % 300 ) % 60 >= 10:
c = ((x % 300 ) % 60) / 10
else:
c = 0
if (int(a)*300) + (int(b)* 60) + (int(c)*10) == x :
print(int(a), int(b), int(c))
else:
print('-1')
n = int(input())
idk(n)
'''