Write a complete C program to read a single string using the input function gets(). Then test whether the string contains all integers, or all alphabets or a combination of both (i.e., alphanumeric). If the string contains all integers, then print the string as it is. If the string contains all alphabets, then check whether the alphabets are in lowercase or uppercase. If any of the characters in the string is in lowercase, then convert them to uppercase, and vice versa. Finally, print the string. On the other hand, if the string is an alphanumeric, then check whether the alphabet(s) in it is/are in lowercase, then convert it/them to uppercase and vice versa. Finally, print the converted string with the same numeric characters as in the original string. Use the output function puts() whenever you are printing the string.
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