This problem is to define four character arrays, input them with scanf and gets respectively, and then output them with puts. The main test is to output the results.

Gets is to input a string of characters, and puts is to output a string of characters.

The focus of this problem is on the terminators of scanf and gets

Enter a string of characters in scanf, which indicates the end of a string of characters when a space or carriage return is encountered.

When you enter a string in gets, it only recognizes the carriage return as the end.

It is wrong to go upstairs. Commas are not allowed, spaces are allowed. Enter the ending symbol of the string, which can only be a space or a carriage return in scanf. When you enter an integer or floating-point number, spaces, commas and carriage returns can be used!