foo.cc: In function 'void sigAdd(int, int)':
foo.cc:51:9: warning: comparison of integer expressions of different signedness: 'int' and 'long unsigned int' [-Wsign-compare]
   51 |     if(x>=sizeof(mana)/sizeof(int)-1)
      |        ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:61:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   61 |     scanf("%d",&n);
      |     ~~~~~^~~~~~~~~
foo.cc:65:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   65 |         scanf("%d%d",&tx,&ty);
      |         ~~~~~^~~~~~~~~~~~~~~~

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