foo.c: In function 'main':
foo.c:6:34: error: invalid operands to binary & (have 'int *' and 'int')
    6 |         scanf("%d %d %d", &a, &b &c);
      |                               ~~ ^
      |                               |
      |                               int *
foo.c:26:16: error: 'o' undeclared (first use in this function)
   26 |         return o;
      |                ^
foo.c:26:16: note: each undeclared identifier is reported only once for each function it appears in

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