foo.c: In function 'main':
foo.c:12:11: warning: unused variable 'na' [-Wunused-variable]
     int x,na; 
           ^~
foo.c:9:12: warning: unused variable 'k' [-Wunused-variable]
  int a[N] ,k;
            ^
foo.c: In function 'Insert':
foo.c:30:8: warning: unused variable 'j' [-Wunused-variable]
  int i,j;
        ^
foo.c: In function 'main':
foo.c:8:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&n);
  ^~~~~~~~~~~~~~
foo.c:11:9: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d", &a[i]);
         ^~~~~~~~~~~~~~~~~~
foo.c:13:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&x);
  ^~~~~~~~~~~~~~

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