foo.cc: In function 'int main()':
foo.cc:40:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   40 |             scanf("%c",&k);
      |             ~~~~~^~~~~~~~~
foo.cc:50:8: warning: 'y' may be used uninitialized in this function [-Wmaybe-uninitialized]
   50 |     DFS(0,x,y);
      |     ~~~^~~~~~~
foo.cc:50:8: warning: 'x' may be used uninitialized in this function [-Wmaybe-uninitialized]

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