foo.c: In function 'Insert':
foo.c:9:29: warning: unused variable 'k' [-Wunused-variable]
    9 |                         int k;
      |                             ^
foo.c: In function 'main':
foo.c:35:13: error: 'i' undeclared (first use in this function)
   35 |         for(i=0;i<=n;i++)
      |             ^
foo.c:35:13: note: each undeclared identifier is reported only once for each function it appears in
foo.c:39:9: error: expected declaration or statement at end of input
   39 |         return 0;
      |         ^~~~~~

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