str1 = "python java c python c++ java java"
str2 = "python c++ c# javascript java c c php"
set1 = set(str1.split())
set2 = set(str2.split())
merge_sets = set1.union(set2)
merge_str = ' '.join(merge_sets)
print(merge_str)
'''
run:
java c++ javascript php c python c#
'''