foo.cc: In function 'void merge(int, int, int)':
foo.cc:58:5: warning: suggest explicit braces to avoid ambiguous 'else' [-Wdangling-else]
   58 |   if(t_x==t_y)
      |     ^
foo.cc: In function 'int main()':
foo.cc:18:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   18 |   scanf("%d",&t);
      |   ~~~~~^~~~~~~~~
foo.cc:19:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   19 |   scanf("%d %d",&x,&y);
      |   ~~~~~^~~~~~~~~~~~~~~

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