foo.c: In function 'main':
foo.c:4:15: warning: missing braces around initializer [-Wmissing-braces]
   int a[2][3]={1,2,3,4,5,6},n;
               ^
                {    }{    }
foo.c: In function 'add':
foo.c:17:8: warning: assignment makes integer from pointer without a cast [-Wint-conversion]
     sum+=p[i];
        ^~

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