/in/foo.c: In function 'main':
/in/foo.c:12:2: warning: implicit declaration of function 'Output' [-Wimplicit-function-declaration]
  Output(a,n);
  ^~~~~~
/in/foo.c: In function 'Insert':
/in/foo.c:17:2: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
  for(i=0;i<n;i++)
  ^~~
/in/foo.c:19:3: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'for'
   for(int j=n-1;j>=i;j--)
   ^~~
/in/foo.c: At top level:
/in/foo.c:24:6: warning: conflicting types for 'Output'
 void Output(int a[],int n)
      ^~~~~~
/in/foo.c:12:2: note: previous implicit declaration of 'Output' was here
  Output(a,n);
  ^~~~~~