text: ﻿String Contains X and Y
  The program must accept a string S as the input. The program must print yes if the string contains only the characters 'X' and 'Y' (case insensitive). Else the program must print no as the output.
  Boundary Condition(s):
  1 <= Length of S <= 100
  Input Format:
  The first line contains S.
  Output Format:
  The first line contains yes or no.
  Example Input/Output 1:
  Input:
  XyxYyXx
  Output:
  yes
  Explanation:
  The string XyxYyXx contains only the characters X and Y (case insensitive).
  So yes is printed.
  Example Input/Output 2:
  Input:
  zyxxy
  Output:
  no
  Python :
  cha="xy"
  stri=input().strip()
  c1,c2=0,0
  for ele in stri:
        if ele.lower() in stri:
          c1=c1+1 
        else:
          c2=c2+11 
  if c2!=0:
      print("no")
  else:
      print("yes")
  cha=input().strip()
  lis=[ele for ele in a.lower()]
  lis=sorted(list(set(lis)))
  if 'x' in lis: remove ('x')
  if 'y' in lis: remove ('y')
  else: print("no")
  cha=input().lower()
  data=list(set(cha))
  test,s=0,0
  for I in data:
      if I=='x' or I=='y':
          s=s+1 
      else:
          test=test+1 
  if s>=1 and test==0:
      print("yes")
  else:
      print("no")
  cha=input()
  cnt=1
  for ele in cha:
      if ele not in "xyXY":
          print("no")
          cnt=0
          break;
  if(cnt==1):
      print("yes")
  C:
  #include<stdio.h>
  int main() {
  char stri[1001];
  scanf("%s",stri);
  for(int ele=0;ele<strlen(stri);ele++)
   {
       if(stri[ele]!='x'&&stri[ele]!='X'&&stri[ele]!='Y'&&stri[ele]!='y')
       {
           printf("no");
           return 0;
       }
  }
  printf("yes");
  }
  
  @ Agent Marvel
  