Problem:
Score : 100 points

Problem Statement

AtCoder Inc. holds a contest every Saturday.

There are two types of contests called ABC and ARC, and just one of them is held at a time.

The company holds these two types of contests alternately: an ARC follows an ABC and vice versa.

Given a string S representing the type of the contest held last week, print the string representing the type of the contest held this week.

Constraints

S is ABC or ARC.

Input

Input is given from Standard Input in the following format:

S

Output

Print the string representing the type of the contest held this week.

Sample Input 1

ABC

Sample Output 1

ARC

They held an ABC last week, so they will hold an ARC this week.

Solution in Python (3.8.2) (judge verdict: Runtime Error)

n,a,b,c = list(map(int,input().split()))
an=0;d={};l=[];x=y=z=0
for i in range(n):
  s=input();l.append(s)
  x+=int(s[0]=='A')
  z+=int(s[-1]=='C')
  y+=int(s[-1]=='B')+int(s[0]=='B')
x=a-x;y=b-y;z=c-z
if (x<0)+(y<0)+(z<0)>=2:
  print("No");exit()
a=[]
for i in range(n):
  if l[i]=='AC':
    if x>=0:
      z+=1;a.append('C')
    else:
      x+=1;a.append('A')
  if l[i]=='AB':
    if x>=0:
      y+=1;a.append('B')
    else:
      x+=1;a.append('A')
  if l[i]=='BC':
    if y>=0:
      z+=1;a.append('C')
    else:
      y+=1;a.append('B')
print("Yes")
for i in a:
  print(i)