foo.cc: In function 'int main()':
foo.cc:45:19: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   45 |      int  t; scanf( " %d " , & t);
      |              ~~~~~^~~~~~~~~~~~~~~
foo.cc:47:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   47 |         scanf( " %d%d " , & N, & M);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~
foo.cc:51:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   51 |             scanf( " %d " , & g[N + 1 + i][i]);
      |             ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
foo.cc:54:29: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   54 |              int  x,y; scanf( " %d%d " , & x, & y);
      |                        ~~~~~^~~~~~~~~~~~~~~~~~~~~~

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