foo.cc: In function 'int main()':
foo.cc:44:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   44 |  scanf("%d%d", &n, &m);
      |  ~~~~~^~~~~~~~~~~~~~~~
foo.cc:46:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   46 |   scanf("%d", a + i);
      |   ~~~~~^~~~~~~~~~~~~
foo.cc:50:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   50 |   scanf("%s", op);
      |   ~~~~~^~~~~~~~~~
foo.cc:52:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   52 |    scanf("%d%d%d", &l, &r, &d);
      |    ~~~~~^~~~~~~~~~~~~~~~~~~~~~
foo.cc:57:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   57 |    scanf("%d%d", &l, &r);
      |    ~~~~~^~~~~~~~~~~~~~~~
foo.cc:61:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   61 |    scanf("%d%d%d", &l, &r, &d);
      |    ~~~~~^~~~~~~~~~~~~~~~~~~~~~
foo.cc:65:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   65 |    scanf("%d", &tnow);
      |    ~~~~~^~~~~~~~~~~~~

Found 6 testcases.
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