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%d%d",a,b,c);
      |                ~^      ~
      |                 |      |
      |                 int *  int
foo.c:6:19: warning: format '%d' expects argument of type 'int *', but argument 3 has type 'int' [-Wformat=]
    6 |         scanf("%d%d%d",a,b,c);
      |                  ~^      ~
      |                   |      |
      |                   int *  int
foo.c:6:21: warning: format '%d' expects argument of type 'int *', but argument 4 has type 'int' [-Wformat=]
    6 |         scanf("%d%d%d",a,b,c);
      |                    ~^      ~
      |                     |      |
      |                     int *  int
foo.c:6:9: warning: 'a' is used uninitialized [-Wuninitialized]
    6 |         scanf("%d%d%d",a,b,c);
      |         ^~~~~~~~~~~~~~~~~~~~~
foo.c:5:9: note: 'a' was declared here
    5 |     int a,b,c;
      |         ^
foo.c:6:9: warning: 'b' is used uninitialized [-Wuninitialized]
    6 |         scanf("%d%d%d",a,b,c);
      |         ^~~~~~~~~~~~~~~~~~~~~
foo.c:5:11: note: 'b' was declared here
    5 |     int a,b,c;
      |           ^
foo.c:6:9: warning: 'c' is used uninitialized [-Wuninitialized]
    6 |         scanf("%d%d%d",a,b,c);
      |         ^~~~~~~~~~~~~~~~~~~~~
foo.c:5:13: note: 'c' was declared here
    5 |     int a,b,c;
      |             ^

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