foo.c:2:21: error: unknown type name 'n'
    2 | int findmax(int a[],n)
      |                     ^
foo.c: In function 'main':
foo.c:26:14: warning: implicit declaration of function 'findmax' [-Wimplicit-function-declaration]
   26 |  int biggest=findmax(a,n);
      |              ^~~~~~~

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