foo.cc: In function 'int main()':
foo.cc:10:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   10 |     scanf("%d%d%d%d",&l,&s,&t,&m);
      |     ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
foo.cc:11:21: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   11 |     For(i,1,m) scanf("%d",&a[i]);
      |                ~~~~~^~~~~~~~~~~~

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