foo.cc: In function 'int main()':
foo.cc:8:8: warning: unused variable 'a' [-Wunused-variable]
    8 |  int x,a=0,m;
      |        ^
foo.cc:17:2: warning: 'm' may be used uninitialized in this function [-Wmaybe-uninitialized]
   17 |  if(m==2)
      |  ^~

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