while True:
    try:
      str = input()
      array = list(str)
      line = [0]*10
      for i in range(0,len(array)):
          if str[i]=='0':
              line[0] = line[0] + 1
          elif str[i]=='1':
              line[1] = line[1] + 1
          elif str[i]=='2':
              line[2] = line[2] + 1
          elif str[i]=='3':
              line[3] = line[3] + 1
          elif str[i]=='4':
              line[4] = line[4] + 1
          elif str[i]=='5':
              line[5] = line[5] + 1
          elif str[i]=='6':
              line[6] = line[6] + 1
          elif str[i]=='7':
              line[7] = line[7] + 1
          elif str[i]=='8':
              line[8] = line[8] + 1
          elif str[i]=='9':
              line[9] = line[9] + 1
      max = line[0]
      maxindex = 0
      for i in range(1 ,10):
         if(max < line[i]):
             max = line[i]
             maxindex = i
      print(maxindex)
    except:
        break