foo.c: In function 'main':
foo.c:37:6: warning: unused variable 'n' [-Wunused-variable]
   37 |  int n=0,x,i=0,f=0,a[100]={0},j;
      |      ^
foo.c:38:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   38 |  scanf("%d %s",&x,s);
      |  ^~~~~~~~~~~~~~~~~~~

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