Problem:
 Score : 100 points    Problem Statement On the Planet AtCoder, there are four types of bases: A , C , G and T . A bonds with T , and C bonds with G .  You are given a letter b as input, which is A , C , G or T . Write a program that prints the letter representing the base that bonds with the base b .      Constraints  b is one of the letters A , C , G and T .         Input Input is given from Standard Input in the following format:  b       Output Print the letter representing the base that bonds with the base b .        Sample Input 1 A      Sample Output 1 T       Sample Input 2 G      Sample Output 2 C

Solution (Python):
s = input()
if s=='A':
    print('T')
elif s=='T':
    print('A')
elif s=='C':
    print('G')
else:
    print('C')

Solution (Python):
b=input()
if b=="A":
    print("T")
elif b=="T":
    print("A")
elif b=="C":
    print("G")
else:
    print("C")

Solution (Python):
b = input()

base_map = dict()
base_map["A"] = "T"
base_map["T"] = "A"
base_map["C"] = "G"
base_map["G"] = "C"

print(base_map[b])

Solution (Python):
enki=input()
if enki=="A":
  print("T")
elif enki=="T":
  print("A")
elif enki=="C":
  print("G")
else:
  print("C")

Solution (Python):
a=input()
if a=='A':
    print('T')
elif a=='T':
    print('A')
elif a=='C':
    print('G')
elif a=='G':
    print('C')

Solution (Python):
a = str(input())
if a == 'A':
  print('T')
elif a == 'T':
  print('A')
elif a == 'G':
  print('C')
else:
  print('G')

Solution (Python):



code_dict = {"A":"T",
             "T":"A",
             "G":"C",
             "C":"G"}

print(code_dict[input()])

Solution (Python):
b = input()

if b=='A':
  print('T')
elif b=='T':
  print('A')
elif b=='G':
  print('C')
else:
  print('G')

Solution (Python):
b=input()
if "A" in b:
    print("T")
elif "G" in b:
    print("C")
elif "C" in b:
    print("G")
elif "T" in b:
    print("A")

Solution (Python):
enki={'A':'T','T':'A','G':'C','C':'G'}
s=str(input())
print(enki[s])

Solution (Python):
a=input()
if a=='G':
  print('C')
elif a=='C':
  print('G')
elif a=='A':
  print('T')
else:
  print('A')

Solution (Python):
b = input()
if b == "A":
    print("T")
elif b == "T":
    print("A")
elif b == "G":
    print("C")
elif b == "C":
    print("G")

Solution (Python):
b=input()
if b=='A':
    print('T')
elif b=='T':
    print('A')
elif b=='C':
    print('G')
elif b=='G':
    print('C')

Solution (Python):
b = input()
if b == 'A':
    print('T')
elif b == 'T':
    print('A')
elif b == 'G':
    print('C')
elif b == 'C':
    print('G')

Solution (Python):
b = input()
if b == "A":
    print("T")
elif b == "T":
    print("A")
elif b == "C":
    print("G")
else:
    print("C")

Solution (Python):
print({'A':'T','C':'G','T':'A','G':'C'}[input()])

Solution (Python):
b = input()
c = {'A': 'T', 'T': 'A', 'C': 'G', 'G': 'C'}
print(c[b])

Solution (Python):
base = {'A': 'T', 'T': 'A', 'C': 'G', 'G': 'C'}
print(base[input()])

Solution (Python):
b = input()
if b == "A":
    print("T")
elif b == "C":
    print("G")
elif b == "G":
    print("C")
else:
    print("A")

Solution (Python):
b = input()
base = ['A', 'C', 'T', 'G'] 
print(base[(base.index(b) + 2 ) % 4])

Solution (Python):
b=input()
if b=="A":
    print("T")
if b=="T":
    print("A")
if b=="C":
    print("G")
if b=="G":
    print("C")

Solution (Python):
ary = ['A', 'C', 'G', 'T']
ans = ['T', 'G', 'C', 'A']

b = input()

print(ans[ary.index(b)])

Solution (Python):
b = input()
if b == "A":
    print("T")
elif b == "C":
    print("G")
elif b == "G":
    print("C")
elif b == "T":
    print("A")

Solution (Python):
b = input()

if b == 'A':
    print('T')
elif b == 'T':
    print('A')
elif b == 'C':
    print('G')
else:
    print('C')

Solution (Python):
b = str(input())
pattern = {'A':'T','T':'A','C':'G','G':'C'}
print(pattern[b])

Solution (Python):
dic = {'A':'T', 'T':'A', 'C':'G', 'G':'C'}
print(dic[input()])

Solution (Python):
b=input()
if b=="A":
    print("T")
elif b=="T":
    print("A")
elif b=="C":
    print("G")
else:
    print("C")

Solution (Python):
n = input()

if n == "A":
  print("T")
if n == "T":
  print("A")
if n == "G":
  print("C")
if n =="C":
  print("G")

Solution (Python):
s=input()
if s=='A':print('T')
elif s=='T':print('A')
elif s=='G':print('C')
elif s=='C':print('G')

Solution (Python):
b=input()
if b=="T":
  print("A")
elif b=="A":
  print("T")
elif b=="G":
  print("C")
else:
  print("G")

Solution (Python):



































def calculation(lines):
    line = lines[0]
    
    
    
    
    
    
    
    
    
    

    if line == 'A':
        result = 'T'
    if line == 'T':
        result = 'A'
    if line == 'C':
        result = 'G'
    if line == 'G':
        result = 'C'

    return [result]



def get_input_lines(lines_count):
    lines = list()
    for _ in range(lines_count):
        lines.append(input())
    return lines



def get_testdata(pattern):
    if pattern == 1:
        lines_input = ['A']
        lines_export = ['T']
    if pattern == 2:
        lines_input = ['G']
        lines_export = ['C']
    return lines_input, lines_export



def get_mode():
    import sys
    args = sys.argv
    if len(args) == 1:
        mode = 0
    else:
        mode = int(args[1])
    return mode



def main():
    import time
    started = time.time()
    mode = get_mode()
    if mode == 0:
        lines_input = get_input_lines(1)
    else:
        lines_input, lines_export = get_testdata(mode)

    lines_result = calculation(lines_input)

    for line_result in lines_result:
        print(line_result)

    
    
    
    
    
    
    
    
    
    
    



if __name__ == '__main__':
    main()

Solution (Python):
b = input()

if b == "A":
    print("T")
elif b == "T":
    print("A")
elif b == "C":
    print("G")
else:
    print("C")

Solution (Python):
b=input()
print("A" if b=="T" else "T" if b=="A" else "G" if b=="C" else "C")

Solution (Python):
d = dict({'A': 'T', 'T': 'A', 'C': 'G', 'G': 'C'})
print(d[input()])

Solution (Python):


def main():

    b = input()

    if b == 'A':
        ans = 'T'

    elif b == 'T':
        ans = 'A'

    elif b == 'C':
        ans = 'G'

    elif b == 'G':
        ans = 'C'


    print(ans)


if __name__ == "__main__":
    main()

Solution (Python):
s = input()
if s=='A':
  print('T')
elif s=='T':
  print('A')
elif s=='C':
  print('G')
elif s=='G':
  print('C')

Solution (Python):
b = input()

if b == 'A':
    print('T')
elif b == 'T':
    print('A')
elif b == 'G':
    print('C')
else:
    print('G')

Solution (Python):
b=input()
if b =='A':
    print('T')
elif b=='C':
    print('G')
elif b=='G':
    print('C')
else:
    print('A')

Solution (Python):
b = input()
ans = {'A':'T', 'C': 'G', 'G':'C', 'T':'A'}
print(ans[b])

Solution (Python):
def main():
    b = input()

    if b == 'A':
        print('T')
    elif b == 'T':
        print('A')
    elif b == 'C':
        print('G')
    else:
        print('C')


if __name__ == "__main__":
    main()

Solution (Python):
b = input()
print("A" if b=="T" else "T" if b=="A" else "G" if b=="C" else "C")

Solution (Python):
b = input()
if b == 'A':
  print('T')
elif b == 'T':
  print('A')
elif b == 'C':
  print('G')
else:
  print('C')

Solution (Python):
b=input()
if b=='A': print("T")
if b=="G": print("C")
if b=="C": print("G")
if b=="T": print("A")

Solution (Python):
b=input()
enki={"A":"T","C":"G","T":"A","G":"C"}
print(enki[b])

Solution (Python):
b=input()
L=["A","C","G","T"]
print(L[::-1][L.index(b)])

Solution (Python):
B = {'A':'T', 'T':'A', 'C':'G', 'G':'C'}

print(B[input()])

Solution (Python):
s = input()
if s=="A":
  print("T")
elif s=="T":
  print("A")
elif s=="C":
  print("G")
elif s=="G":
  print("C")

Solution (Python):
b = input()
if b == 'A':
    b = 'T'
elif b == 'T':
    b = 'A'
elif b == 'C':
    b = 'G'
else:
    b = 'C'
print(b)

Solution (Python):
print({'A': 'T', 'C': 'G', 'G': 'C', 'T': 'A'}[input()])

Solution (Python):
a=["A","C","G","T"]
b=["T","G","C","A"]

s=input()

print(b[a.index(s)])

Solution (Python):
import sys

readline = sys.stdin.readline
MOD = 10 ** 9 + 7
INF = float('INF')
sys.setrecursionlimit(10 ** 5)


def main():
    b = input()
    res = {"A": "T", "T": "A", "C": "G", "G": "C"}

    print(res[b])

if __name__ == '__main__':
    main()

Solution (Python):
n = input()
if n == 'A':
    print('T')
elif n == 'T':
    print('A')
elif n == 'C':
    print('G')
else:
    print('C')

Solution (Python):
b = input()
t = {'A': 'T', 'C': 'G', 'T': 'A', 'G': 'C'}
print(t[b])

Solution (Python):
S = input()
mydict = {"A":"T","T":"A","G":"C","C":"G"}
print(mydict[S])

Solution (Python):
b = input()
s = "AGTC"
for i in range(4):
  if s[i] == b:
    print(s[(i+2)%4])

Solution (Python):
a = input()
if a == "A":
  print("T")
elif a == "T":
  print("A")
elif a == "G":
  print("C")
else:
  print("G")

Solution (Python):
b = input()
d = dict()
d['A'] = 'T'
d['T'] = 'A'
d['C'] = 'G'
d['G'] = 'C'

print(d[b])

Solution (Python):
S = str(input())

if S == "A":
  print("T")
elif S == "T":
  print("A")
elif S == "G":
  print("C")
else:
  print("G")

Solution (Python):
b = input()
d = {"A":"T", "T":"A", "C":"G", "G":"C"}
print(d[b])

Solution (Python):
def resolve():
  b = input()
  if b == 'A':
    print('T')
  elif b == 'T':
    print('A')
  elif b == 'C':
    print('G')
  elif b == 'G':
    print('C')
  return

if __name__ == "__main__":
  resolve()

Solution (Python):
b = input()
a = {"A":"T", "T":"A", "C":"G", "G":"C"}
ans = a[b]
print(ans)

Solution (Python):
b = input().strip()
if b=="A":
    print("T")
elif b=="T":
    print("A")
elif b=="C":
    print("G")
else:
    print("C")

Solution (Python):
import sys
def input(): return sys.stdin.readline().strip()
def mapint(): return map(int, input().split())
sys.setrecursionlimit(10**9)

b = input()
if b=='A':
    print('T')
elif b=='T':
    print('A')
elif b=='C':
    print('G')
else:
    print('C')

Solution (Python):
d = {"A": "T", "T": "A", "C": "G", "G": "C"}
print(d[input()])

Solution (Python):
b = input()

if b=="A" or b=="T":
  print("A") if b=="T" else print("T")
else:
  print("C") if b=="G" else print("G")

Solution (Python):
import sys
input = lambda: sys.stdin.readline().rstrip()

def main():
    b = input()
    if b == "A":
        print("T")
    elif b == "T":
        print("A")
    elif b == "C":
        print("G")
    elif b == "G":
        print("C")
            
if __name__ == '__main__':
    main()

Solution (Python):
def main():
 b = input()
 if b == 'A':
     print('T')
 elif b == 'T':
     print('A')
 elif b == 'C':
     print('G')
 elif b == 'G':
     print('C')
main()

Solution (Python):
import sys
b = input()
if not ( b == 'A' or b == 'T' or b == 'G' or b == 'C' ): sys.exit()
base = { 'A':'T', 'T':'A', 'G':'C', 'C':'G' }

print(base[b])

Solution (Python):
import sys
b = input()
if not ( b == 'A' or b == 'T' or b == 'G' or b == 'C' ): sys.exit()

if b == 'T': print('A')
if b == 'A': print('T')
if b == 'C': print('G')
if b == 'G': print('C')

Solution (Python):
import sys
sys.setrecursionlimit(10**7)
input = sys.stdin.readline

b = input().rstrip()

if b == 'A':
    print('T')
if b == 'T':
    print('A')
if b == 'C':
    print('G')
if b == 'G':
    print('C')

Solution (Python):
b=input()
enkitui={"A":"T","T":"A","C":"G","G":"C"}
print(enkitui[b])

Solution (Python):
pair1 = ["A","T"]
pair2 = ["G","C"]

b = input()

if b in pair1:
    pair1.remove(b)
    print(pair1[0])
    
else:
    pair2.remove(b)
    print(pair2[0])

Solution (Python):
b=input()
if b=="A":
  print("T")
elif b=="T":
  print("A")
elif b=="C":
  print("G")
elif b=="G":
  print("C")

Solution (Python):
import sys
sys.setrecursionlimit(10**6)

b = input()

d = {'A':'T','C':'G','T':'A','G':'C'}

print(d[b])

Solution (Python):
import sys
sys.setrecursionlimit(10**8)
def ii(): return int(sys.stdin.readline())
def mi(): return map(int, sys.stdin.readline().split())
def li(): return list(map(int, sys.stdin.readline().split()))
def li2(N): return [list(map(int, sys.stdin.readline().split())) for _ in range(N)]
def dp2(ini, i, j): return [[ini]*i for _ in range(j)]





S = input()
at = 'AT'
gc = 'GC'

if len(at.replace(S, '')) == 1:
    print(at.replace(S, ''))
else:
    print(gc.replace(S, ''))

Solution (Python):
b = input()

if b == 'A':
  print('T')
elif b == 'T':
  print('A')
elif b == 'C':
  print('G')
elif b == 'G':
  print('C')

Solution (Python):
line = input()
if line == "A":
    print("T")
elif line == "T":
    print("A")
elif line == "C":
    print("G")
else:
    print("C")

Solution (Python):
S = input()
if S == 'A':
    print('T')
    exit(0)
if S == 'T':
    print('A')
    exit(0)
if S == 'C':
    print('G')
    exit(0)
if S == 'G':
    print('C')
    exit(0)

Solution (Python):
l = ['A','C','T','G']
b = input()
print(l[l.index(b)-2])

Solution (Python):
d = input()

if d=='A':
    print("T")
elif d=='T':
    print("A")
elif d=='C':
    print("G")
elif d=='G':
    print("C")

Solution (Python):
b = list(input())

for i in range(len(b)):
  if b[i] == "A":
    b[i] = "T"
  elif b[i] == "T":
    b[i] = "A"
  elif b[i] == "C":
    b[i] = "G"
  else:
    b[i] = "C"
    
print("".join(b))

Solution (Python):
b = input()
if b == "A":
  print("T")
elif b == "T":
  print("A")
elif b == "C":
  print("G")
else:
  print("C")

Solution (Python):
b = input()

if b == 'A':
    print('T')
elif b == 'C':
    print('G')
elif b == 'G':
    print('C')
else:
    print('A')

Solution (Python):
b = input()
if b == "A" : 
    print('T')
elif b == "C":
    print("G")
elif b == "G":
    print("C")
else:
    print("A")

Solution (Python):
b = input()
Base = ['A','T','G','C']
Pair = ['T','A','C','G']
print(Pair[Base.index(b)])

Solution (Python):
dict_1 = {"A":"T","G":"C"}
dict_2 = {"T":"A","C":"G"}

s = input()
if s in dict_1:
  ans = dict_1[s]
else:
  ans = dict_2[s]

print(ans)

Solution (Python):
a = {'A':'T','T':'A','G':'C','C':'G'}
print(a[input()])

Solution (Python):
b = input()
if b == "A":
    print("T")
elif b == "T":
    print("A")
elif b == "G":
    print("C")
else:
    print("G")

Solution (Python):
b = input()

if b == 'A':
    print('T')
elif b == 'T':
    print('A')
elif b == 'C':
    print('G')
else:
    print('C')

Solution (Python):
S = input()
ans = ""
if S == "A":
  ans = "T"
elif S == "T":
  ans = "A"
elif S == "C":
  ans = "G"
elif S == "G":
  ans = "C"

print(ans)

Solution (Python):
b=input()
if b=="A":
  print("T")
elif b=="T":
  print("A")
elif b=="C":
  print("G")
else:
  print("C")

Solution (Python):
b = input()
AC = ["A", "C"]
GT = ["G", "T"]

if b in AC:
    b = GT[b == "A"]
    
elif b in GT:
    b = AC[b == "G"]
    
print(b)

Solution (Python):
b = str(input())
if b == "A":
    print("T")
elif b == "C":
    print("G")
elif b == "G":
    print("C")
elif b == "T":
    print("A")

Solution (Python):
import sys
rr = lambda: sys.stdin.readline().rstrip()
a = rr()
if a in 'AT':
  print('AT'.replace(a, ''))
else:
  print('GC'.replace(a, ''))

Solution (Python):
b = input()
if b == "A":
  print("T")
elif b == "T":
  print("A")
elif b == "C":
  print("G")
else:
  print("C")

Solution (Python):

d = {
	'A':'T', 
	'C':'G', 
	'T':'A',
	'G':'C'
}
print(d[input()])

Solution (Python):
x=input()
if x=="A":
  print("T")
if x=="T":
  print("A")
if x=="G":
  print("C")
if x=="C":
  print("G")

Solution (Python):
b = input()
x = ['A', 'C', 'T', 'G']

for i in range(4):
    if b == x[i]:
        print(x[(i + 2) % 4])
        break

Solution (Python):
b = input()

if b == "A":
  print("T")
if b == "T":
  print("A")
if b == "C":
  print("G")
if b == "G":
  print("C")

Solution (Python):
b = input()
if b in ["A","T"]:
  if b=="A":print("T")
  else: print("A")
else:
  if b=="C":print("G")
  else: print("C")

Solution (Python):
D = {'A': 'T', 'T':'A', 'G':'C', 'C':'G'}
b = input()
print(D[b])

Solution (Python):
print({'A':'T','T':'A','G':'C','C':'G'}.get(input()))

Solution (Python):
print({'A':'T', 'T':'A', 'C':'G', 'G':'C'}[input()])

Solution (Python):
s=input()
if s=='A':
    print('T')
elif s=='T':
    print('A')
elif s=='C':
    print('G')
elif s=='G':
    print('C')

Solution (Python):
b = input()

if b == "A":
    print("T")
elif b == "T":
    print("A")
elif b == "G":
    print("C")
else:
    print("G")

Solution (Python):
b = input()

if b == "A":
    print("T")
elif b == "T":
    print("A")
elif b == "C":
    print("G")
elif b == "G":
    print("C")

Solution (Python):
a = input()

if a == 'A':
    print('T')
elif a == 'T':
    print('A')
elif a == 'C':
    print('G')
elif a == 'G':
    print('C')

Solution (Python):
A = {"A": "T", "T": "A", "C": "G", "G": "C"}
print(A[input()])

Solution (Python):
b = input()
if b == "A":
    print("T")
elif b == "T":
    print("A")
elif b == "G":
    print("C")
elif b == "C":
    print("G")

Solution (Python):
b = str(input())
dic = {"A":"T","T":"A","G":"C","C":"G"}
print(dic[b])

Solution (Python):
b=input()

print(b.translate(str.maketrans({"A":"T","T":"A","C":"G","G":"C"})))

Solution (Python):
b = input()

if b == 'A':
    print('T')
elif b == 'T':
    print('A')
elif b == 'C':
    print('G')
else:
    print('C')

Solution (Python):
b=input()
if b=="A":
    print("T")
if b=="T":
    print("A")
if b=="C":
    print("G")
if b=="G":
    print("C")

Solution (Python):
k = input()
if k == "A":
  print("T")
if k == "C":
  print("G")
if k == "G":
  print("C")
if k == "T":
  print("A")

Solution (Python):
b = input()
if b=='T':
  print('A')
elif b=='A':
  print('T')
elif b=='C':
  print('G')
else:
  print('C')

Solution (Python):


b = input()
if b == 'A':
    print('T')
elif b == 'T':
    print('A')
elif b == 'C':
    print('G')
else:
    print('C')

Solution (Python):
b=input()
if b=="A":
  print("T")
elif b=="T":
  print("A")
elif b=="G":
  print("C")
else:
  print("G")

Solution (Python):
x = input()
if x == 'A': print('T')
elif x == 'T': print('A')
elif x == 'G': print('C')
else: print('G')

Solution (Python):
s = str(input())

if s == 'A':
    print('T')
elif s == 'T':
    print('A')
elif s == 'C':
    print('G')
else:
    print('C')

Solution (Python):
b=input()
print('A' if b=='T' else 'T' if b=='A' else 'G' if b=='C' else 'C')

Solution (Python):
import sys

input = sys.stdin.readline


def main():
    b = input().rstrip()

    if b == "A":
        ans = "T"
    elif b == "T":
        ans = "A"
    elif b == "G":
        ans = "C"
    else:
        ans = "G"

    print(ans)


if __name__ == "__main__":
    main()

Solution (Python):
print('TCG A'[ord(input())%5])

Solution (Python):
print('TCG A'[ord(input())%5])

Solution (Python):
s=input()
if s=="A":
    print("T")
elif s=="T":
    print("A")
elif s=="G":
    print("C")
else:
    print("G")

Solution (Python):
b=input()
print('A' if b=='T' else 'T' if b=='A' else 'G' if b=='C' else 'C')

Solution (Python):
b = input()
if b == "A":  print("T")
elif b == "T": print("A")
elif b == "C": print("G")
elif b == "G": print("C")

Solution (Python):
dic = {"A":"T","T":"A","G":"C","C":"G"}
print(dic[input()])

Solution (Python):


enki = {'A':'T', 'T':'A', 'C':'G', 'G':'C'}

b = str(input())

print(enki[b])

Solution (Python):
b = input()
if b == 'A':
    print('T')
elif b == 'C':
    print('G')
elif b == 'G':
    print('C')
else:
    print('A')

Solution (Python):
h = {"A": "T", "T": "A", "C": "G", "G": "C"}
print(h[input()])

Solution (Python):


a = input()
r = ''
if a == 'A':
  print('T')
elif a == 'T':
  print('A')
elif a == 'G':
  print('C')
elif a == 'C':
  print('G')

Solution (Python):
d={"A":"T","G":"C","T":"A","C":"G"};print(d[input()])

Solution (Python):
dic = {"A":"T","T":"A","G":"C","C":"G"}
b=input()
print(dic[b])

Solution (Python):
b=input().strip()
a = {'A':'T', 'T':'A', 'C':'G', 'G':'C'}
print(a[b])

Solution (Python):
B = input()

X = 'ATCG'
Y = 'TAGC'

print(Y[X.index(B)])

Solution (Python):
g=input()
if g=='A':
  print('T')
if g=='T':
  print('A')
  
if g=='C':
  print('G')
  
if g=='G':
  print('C')

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

if n == "A":
    print("T")
elif n == "T":
    print("A")
elif n == "C":
    print("G")
else:
    print("C")

Solution (Python):
s = input()

if s == "A":
    print("T")
elif s == "T":
    print("A")
elif s == "G":
    print("C")
else:
    print("G")

Solution (Python):
s = input()
if s == 'A':
  print('T')
elif s == 'T':
  print('A')
elif s == 'G':
  print('C')
elif s == 'C':
  print('G')

Solution (Python):
n = input()
print({'A': 'T', 'T': 'A', 'C': 'G', 'G': 'C'}[n])

Solution (Python):
def main():
    b = str(input())
    if b == 'A':
        print('T')
    elif b == 'T':
        print('A')
    elif b == 'C':
        print('G')
    else:
        print('C')

main()

Solution (Python):
b = input()
if b == "A":
    print("T")
elif b == "T":
    print("A")
elif b == "C":
    print("G")
elif b == "G":
    print("C")

Solution (Python):
b=input()
if b=='A':
    print('T')
elif b=='T':
    print('A')
elif b=='C':
    print('G')
elif b=='G':
    print('C')

Solution (Python):
b=input()

if b=="A":
    print("T")
elif b=="T":
    print("A")
elif b=="G":
    print("C")
else:
    print("G")

Solution (Python):
d = {"A":"T","T":"A","C":"G","G":"C"}
print(d[input()])

Solution (Python):
b=input()
d={"A":"T","T":"A","C":"G","G":"C"}
print(d[b])

Solution (Python):
b = input()

if b =="A":
    print("T")
elif b =="T":
    print("A")
elif b =="C":
    print("G")
elif b =="G":
    print("C")

Solution (Python):
b = input()
print("A" if b=="T" else "T" if b=="A" else "C" if b=="G" else "G")

Solution (Python):
b=input()
print("A" if b=="T" else "T" if b=="A" else "G" if b=="C" else "C")

Solution (Python):
def main():
    d = {"A":"T", "T":"A", "G":"C", "C":"G"}
    print(d[input()])
    
if __name__ == "__main__":
    main()

Solution (Python):
b = input()

if b=="A":
    print("T")
elif b == "T":
    print("A")
elif b == "C":
    print("G")
else:
    print("C")

Solution (Python):
b=input()
l={'A':'T','T':'A','C':'G','G':'C'}
print(l[b])

Solution (Python):
b = raw_input()
h = {'A':'T','C':'G','G':'C','T':'A'}
print h[b]

Solution (Python):
def solve():
    b = input()
    if b == 'A':
        print('T')
    elif b == 'T':
        print('A')
    elif b == 'C':
        print('G')
    elif b == 'G':
        print('C')


if __name__ == '__main__':
    solve()

Solution (Python):
b = input()
for c in b:
    if c == 'A':
        print('T', end='')
    elif c == 'C':
        print('G', end='')
    elif c == 'G':
        print('C', end='')
    elif c == 'T':
        print('A', end='')
print()

Solution (Python):
a=input()
if a=="A":
  print("T")
elif a=="T":
  print("A")
elif a=="C":
  print("G")
else:
  print("C")

Solution (Python):
d = {
    'A':'T',
    'T':'A',
    'C':'G',
    'G':'C'}

print(''.join(d[c] for c in input()))

Solution (Python):
b = input()
print({'A':'T','T':'A','C':'G','G':'C'}[b])

Solution (Python):
b = input()

if b == 'A':
    print('T')
elif b == 'T':
    print('A')
elif b == 'C':
    print('G')
elif b == 'G':
    print('C')

Solution (Python):
b = input()
d = {'A': 'T', 'T': 'A', 'C': 'G', 'G': 'C'}
print(d[b])

Solution (Python):
import sys

b = sys.stdin.readline().strip()
dic = {"A": "T", "T": "A", "C": "G", "G": "C"}
print(dic[b])

Solution (Python):
b = input()

d = {"A":"T","C":"G","G":"C","T":"A"}

print(d[b])

Solution (Python):
import sys

read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readline_s = sys.stdin.readline
readlines = sys.stdin.buffer.readlines


def main():
    b = readline_s().rstrip()

    if b == 'A':
        ans = 'T'
    elif b == 'T':
        ans = 'A'
    elif b == 'C':
        ans = 'G'
    elif b == 'G':
        ans = 'C'

    print(ans)


if __name__ == '__main__':
    main()

Solution (Python):

b = input()
if b == 'A':
    print('T')
elif b == 'T':
    print('A')
elif b == 'G':
    print('C')
else:
    print('G')

Solution (Python):
b = input()

pair = {"A": "T", "T": "A", "C": "G", "G": "C"}
print(pair[b])

Solution (Python):
S=input()
if S=="A":
  print("T")
elif S=="T":
  print("A")
elif S=="G":
  print("C")
else:
  print("G")

Solution (Python):
s=input()
if s == 'A':
  print('T')
elif s == 'T':
  print('A')
elif s == 'G':
  print('C')
elif s == 'C':
  print('G')

Solution (Python):

b = input()
t = {"A":"T","T":"A", "C":"G","G":"C"}

result = ""

for i in b:
    result += t[i]
    
print(result)

Solution (Python):
b = input()

if b == 'A':
    print('T')
elif b == 'T':
    print('A')
elif b == 'G':
    print('C')
elif b == 'C':
    print('G')

Solution (Python):
b = input()
if b == 'A':
    print('T')
elif b == 'T':
    print('A')
elif b == 'C':
    print('G')
else:
    print('C')

Solution (Python):
b = input()
AT = ["A", "T"]
CG = ["C", "G"]

if b in AT:
  AT.remove(b)
  print(AT[0])
else:
  CG.remove(b)
  print(CG[0])

Solution (Python):
b=input()
c={'A':'T','T':'A','G':'C','C':'G'}
print(c[b])

Solution (Python):
b = input()

if b == 'A':
  ans = 'T'
elif b == 'T':
  ans = 'A'
elif b == 'C':
  ans = 'G'
else:
  ans = 'C'

print(ans)

Solution (Python):
b = input()
if b == "A":
  print("T")
elif b == "T":
  print("A")
elif b == "G":
  print("C")
else:
  print("G")

Solution (Python):
a=['A','C','G','T']
b=['T','G','C','A']
print(b[a.index(input())])

Solution (Python):
b=input()
if b=="A":
  print("T")
elif b=="C":
  print("G")
elif b=="G":
  print("C")
elif b=="T":
  print("A")

Solution (Python):
b = input()

if b == "A":
    print("T")
elif b == "T":
    print("A")
elif b == "C":
    print("G")
else:
    print("C")

Solution (Python):
b = input()

print('T' if b == 'A' else 'A' if b =='T' else 'C' if b == 'G' else 'G')

Solution (Python):
b = input()

if b == 'A':
  print('T')
elif b == 'T':
  print('A')
elif b == 'C':
  print('G')
else:
  print('C')

Solution (Python):
b=input()
if b=='A':print('T')
if b=='T':print('A')
if b=='C':print('G')
if b=='G':print('C')

Solution (Python):
b = input()
if b == "A":
    print("T")
elif b == "T":
    print("A")
elif b == "G":
    print("C")
else:
    print("G")

Solution (Python):

s=input()

if s=="A":
  ans="T"
elif s=="T":
  ans="A"
elif s=="C":
  ans="G"
else:
  ans="C"
  
print(ans)

Solution (Python):
print({"A":"T","T":"A","C":"G","G":"C"}[input()])

Solution (Python):
s=input()
hairetsu=[["A","T"],["T","A"],["G","C"],["C","G"]]
for i in range(4):
    if s==hairetsu[i][0]:
        print(hairetsu[i][1])

Solution (Python):
b = input()

if b == 'A':
    print('T')
elif b == 'T':
    print('A')
elif b == 'C':
    print('G')
elif b == 'G':
    print('C')

Solution (Python):
a = input()
print("A" if a == "T" else "T" if a == "A" else "C" if a == "G" else "G")

Solution (Python):
b = input()
x = {'A': 'T', 'C':'G', 'G': 'C', 'T': 'A'}
print(x[b])

Solution (Python):
b = input()

print("A" if b=="T" else "T" if b=="A" else "C" if b=="G" else "G")

Solution (Python):
b = str(input())
print("A" if b == "T" else "T" if b == "A" else "C" if b == "G" else "G")

Solution (Python):
b = input()

if b == 'A':
    print('T')
elif b == 'T':
    print('A')
elif b == 'C':
    print('G')
elif b == 'G':
    print('C')

Solution (Python):
b = input()
if b == 'A':
    print('T')
elif b == 'C':
    print('G')
elif b == 'G':
    print('C')
else:
    print('A')

Solution (Python):
b=input()
if b=='A':
    print('T')
elif b=='T':
    print('A')
elif b=='G':
    print('C')
else:
    print('G')

Solution (Python):
b=input()

X=['A','C','G','T']
Y=['T','G','C','A']

for i in range(4):
  if b==X[i]:
    print(Y[i])

Solution (Python):
b = input()












pattern = {
    'A':'T',
    'T':'A',
    'C':'G',
    'G':'C'
}

print(pattern[b])

Solution (Python):
b = input()

if b == 'A':
    print('T')
elif b == 'T':
    print('A')
elif b == 'C':
    print('G')
elif b == 'G':
    print('C')
else:
    pass

Solution (Python):
b=input()
if b=='A':
    print('T')
if b=='T':
    print('A')
if b=='C':
    print('G')
if b=='G':
    print('C')

Solution (Python):
b=input()
if b in 'A':print('T')
elif b in 'T':print('A')
elif b in 'C':print('G')
else:print('C')

Solution (Python):
b = input()
if(b == 'A'):
  print('T')
elif(b == 'T'):
  print('A')
elif(b == 'G'):
  print('C')
else:
  print('G')

Solution (Python):
s = input()
if s=='A': print("T")
if s=='T': print("A")
if s=='C': print("G")
if s=='G': print("C")

Solution (Python):
b = input()

ans = {'A': 'T', 'C':'G', 'T':'A', 'G':'C'}
print(ans[b])

Solution (Python):
b = input()
if b == 'A':
    print ('T')
elif b == 'T':
    print ('A')
elif b == 'C':
    print ('G')
else:
    print ('C')

Solution (Python):
a = input()
if a == 'A':
    print('T')
elif a == 'T':
    print('A')
elif a == 'C':
    print('G')
else:
    print('C')

Solution (Python):
b = input()
d = {'A':'T', 'T':'A', 'C':'G', 'G':'C'}
print(d[b])

Solution (Python):
b = input()
if b == "A":
    print("T")
elif b == "T":
    print("A")
elif b == "G":
    print("C")
else:
    print("G")

Solution (Python):
from collections import defaultdict, deque
import sys

INF = float('inf')
def LI(): return list(map(int, sys.stdin.buffer.readline().split()))
def I(): return int(sys.stdin.buffer.readline())
def LS(): return sys.stdin.buffer.readline().rstrip().decode('utf-8').split()
def S(): return sys.stdin.buffer.readline().rstrip().decode('utf-8')
def IR(n): return [I() for i in range(n)]
def LIR(n): return [LI() for i in range(n)]
def SR(n): return [S() for i in range(n)]
def LSR(n): return [LS() for i in range(n)]
def SRL(n): return [list(S()) for i in range(n)]
def MSRL(n): return [[int(j) for j in list(S())] for i in range(n)]


b = S()
ans = 'T' if b == 'A' else 'A' if b == 'T' else 'C' if b == 'G' else 'G'
print(ans)

Solution (Python):
b=input()
ans=""
if b=="A":
  ans="T"
elif b=="C":
  ans="G"
elif b=="G":
  ans="C"
elif b=="T":
  ans="A"
print(ans)

Solution (Python):


b = str(input())


if b == "A":
    print("T")
elif b == "T":
    print("A")
elif b == "C":
    print("G")
else:
    print("C")

Solution (Python):
b= input()
if b=="A":
    print("T")
elif b=="T":
    print("A")
elif b=="C":
    print("G")
elif b=="G":
    print("C")

Solution (Python):


d = {'A':'T', 'T':'A', 'C':'G', 'G':'C'}
print(d[input()])

Solution (Python):
print('ACGT'['TGCA'.find(input())])

Solution (Python):
b = input()

if(b=="A"):
  print("T")
elif(b=="T"):
  print("A")
elif(b=="G"):
  print("C")
else:
  print("G")

Solution (Python):
b={'A':'T','C':'G','G':'C','T':'A'}
print(b[input()])

Solution (Python):
def main():
  b=input()
  if b=='A':
    print('T')
  elif b=='T':
    print('A')
  elif b=='C':
    print('G')
  else:
    print('C')
    
main()

Solution (Python):
b = input()

if b == 'A':
  print('T')
elif b == 'T':
  print('A')
elif b == 'C':
  print('G')
else:
  print('C')

Solution (Python):
b = input()

if b == "A":
    print("T")
elif b == "C":
    print("G")
elif b == "G":
    print("C")
else:
    print("A")

Solution (Python):
b=input()

if b=="A":
  print("T")
elif b=="T":
  print("A")
elif b=="C":
  print("G")
else:
  print("C")

Solution (Python):
print({'A':'T','T':'A','G':'C','C':'G'}[input()])

Solution (Python):
b=input()
if b == 'A': print('T')
elif b == 'T': print('A')
elif b == 'C': print('G')
elif b == 'G': print('C')

Solution (Python):
b = str(input())
if b == 'A':
    print('T')
elif b == 'C':
    print('G')
elif b == 'G':
    print('C')
else:
    print('A')

Solution (Python):

import sys
input = sys.stdin.readline
b =input().strip()
ans =""
if b=="A":
    ans="T"
elif b =="T":
    ans ="A"
elif b =="C":
    ans ="G"
elif b =="G":
    ans ="C"
print(ans)

Solution (Python):
a='ACGT';b='TGCA'
print(b[a.index(input())])

Solution (Python):
b=input()
print('A' if b=='T' else 'T' if b=='A' else 'C' if b=='G' else 'G')

Solution (Python):
b = str(input())
if b == 'A':
    print('T')
elif b == 'T':
    print('A')
elif b == 'C':
    print('G')
else:
    print('C')

Solution (Python):
def main():
    b = input()
    if b == "A":
        print("T")
    elif b == "T":
        print("A")
    elif b == "G":
        print("C")
    elif b == "C":
        print("G")


if __name__ == '__main__':
    main()