foo.cc: In function 'int main()':
foo.cc:5:10: warning: unused variable 'c' [-Wunused-variable]
    5 |  int a,b,c,d,e;
      |          ^
foo.cc:5:12: warning: unused variable 'd' [-Wunused-variable]
    5 |  int a,b,c,d,e;
      |            ^
foo.cc:5:14: warning: unused variable 'e' [-Wunused-variable]
    5 |  int a,b,c,d,e;
      |              ^
foo.cc:16:8: warning: 'b' may be used uninitialized in this function [-Wmaybe-uninitialized]
   16 |  cout<<b<<endl;
      |        ^

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