foo.c:4:4: error: expected declaration specifiers or '...' before 'strcat'
    4 | (  strcat(a,b);
      |    ^~~~~~
foo.c:5:4: error: expected declaration specifiers or '...' before 'strcat'
    5 |    strcat(b,a);
      |    ^~~~~~
foo.c:3:6: error: 'play' declared as function returning a function
    3 | void play(char a[],char b[])
      |      ^~~~
foo.c: In function 'play':
foo.c:10:1: error: expected '=', ',', ';', 'asm' or '__attribute__' before '{' token
   10 | {  int n=0;
      | ^
foo.c:22: error: expected '{' at end of input
foo.c:22: warning: control reaches end of non-void function [-Wreturn-type]

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