foo.c: In function 'main':
foo.c:11:25: warning: format '%d' expects argument of type 'int *', but argument 2 has type 'int' [-Wformat=]
   11 |                 scanf("%d %d",a[i],b[i]);
      |                        ~^     ~~~~
      |                         |      |
      |                         int *  int
foo.c:11:28: warning: format '%d' expects argument of type 'int *', but argument 3 has type 'int' [-Wformat=]
   11 |                 scanf("%d %d",a[i],b[i]);
      |                           ~^       ~~~~
      |                            |        |
      |                            int *    int
foo.c:11:17: warning: 'b' is used uninitialized [-Wuninitialized]
   11 |                 scanf("%d %d",a[i],b[i]);
      |                 ^~~~~~~~~~~~~~~~~~~~~~~~
foo.c:6:13: note: 'b' declared here
    6 |         int b[7];
      |             ^
foo.c:11:17: warning: 'a' is used uninitialized [-Wuninitialized]
   11 |                 scanf("%d %d",a[i],b[i]);
      |                 ^~~~~~~~~~~~~~~~~~~~~~~~
foo.c:5:9: note: 'a' declared here
    5 |     int a[7];
      |         ^

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