foo.c: In function 'main':
foo.c:4:15: warning: 'x' is used uninitialized [-Wuninitialized]
    4 |         int x,y=x,n=0;
      |               ^
foo.c:4:13: note: 'x' declared here
    4 |         int x,y=x,n=0;
      |             ^
foo.c:18:17: warning: array subscript -1 is below array bounds of 'int[10]' [-Warray-bounds]
   18 |                 printf("%d",a[n]);
      |                 ^~~~~~~~~~~~~~~~~
foo.c:12:21: note: while referencing 'a'
   12 |                 int a[10]={0};
      |                     ^

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