foo.cc: In function 'int main()':
foo.cc:45:7: warning: unused variable 'length' [-Wunused-variable]
   45 |   int length=r-l+1;
      |       ^~~~~~
foo.cc:36:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   36 |  scanf("%d %d %d",&n1,&n2,&q);
      |  ~~~~~^~~~~~~~~~~~~~~~~~~~~~~
foo.cc:37:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   37 |  scanf("%s",a+1);
      |  ~~~~~^~~~~~~~~~
foo.cc:38:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   38 |  scanf("%s",b+1);
      |  ~~~~~^~~~~~~~~~
foo.cc:44:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   44 |   scanf("%d %d",&l,&r);
      |   ~~~~~^~~~~~~~~~~~~~~

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