foo.c: In function 'main':
foo.c:5:10: error: 'n' undeclared (first use in this function)
  int i,a[n];
          ^
foo.c:5:10: note: each undeclared identifier is reported only once for each function it appears in
foo.c:7:13: error: stray '\' in program
  scanf("%d",\n);
             ^
foo.c:5:8: warning: unused variable 'a' [-Wunused-variable]
  int i,a[n];
        ^

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