foo.cc: In function 'void init()':
foo.cc:23:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   23 |     scanf("%d",&n);
      |     ~~~~~^~~~~~~~~
foo.cc:24:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   24 |     scanf("%d%d%d",&c1,&c2,&c3);
      |     ~~~~~^~~~~~~~~~~~~~~~~~~~~~
foo.cc:27:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   27 |         scanf("%d%d",&p[i].a,&p[i].b);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

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