foo.c: In function 'main':
foo.c:6:17: warning: format '%d' expects argument of type 'int *', but argument 2 has type 'int' [-Wformat=]
    6 |         scanf("%d",n);
      |                ~^  ~
      |                 |  |
      |                 |  int
      |                 int *
foo.c:13:16: warning: statement with no effect [-Wunused-value]
   13 |          num[0]==1;
      |          ~~~~~~^~~
foo.c:14:16: warning: statement with no effect [-Wunused-value]
   14 |          num[1]==1;
      |          ~~~~~~^~~
foo.c:10:13: warning: array subscript 0 is outside array bounds of 'int[<Ub120>]' [-Warray-bounds]
   10 |          num[a]=0;
      |          ~~~^~~
foo.c:7:13: note: while referencing 'num.3'
    7 |         int num[n];
      |             ^~~

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