foo.c: In function 'findmax':
foo.c:3:2: error: 'max' undeclared (first use in this function)
    3 | {max=a[0];
      |  ^~~
foo.c:3:2: note: each undeclared identifier is reported only once for each function it appears in
foo.c:7:12: error: expected ';' before '}' token
    7 |  return max
      |            ^
      |            ;
    8 | }
      | ~           
foo.c:8:1: warning: control reaches end of non-void function [-Wreturn-type]
    8 | }
      | ^

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