foo.cc: In function 'int main()':
foo.cc:67:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d",&N);
     ~~~~~^~~~~~~~~
foo.cc:69:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%lld",&arr[i]);
         ~~~~~^~~~~~~~~~~~~~~~
foo.cc:73:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d",&M);
     ~~~~~^~~~~~~~~
foo.cc:77:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d",&K);
         ~~~~~^~~~~~~~~
foo.cc:79:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
             scanf("%d %d %lld",&L, &R, &C);
             ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
foo.cc:83:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
             scanf("%d %d",&L,&R);
             ~~~~~^~~~~~~~~~~~~~~

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