foo.cc: In function 'int main()':
foo.cc:5:8: warning: variable 'b' set but not used [-Wunused-but-set-variable]
    5 |  int a,b,c,d,e;
      |        ^
foo.cc:5:10: warning: variable 'c' set but not used [-Wunused-but-set-variable]
    5 |  int a,b,c,d,e;
      |          ^
foo.cc:5:12: warning: variable 'd' set but not used [-Wunused-but-set-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;
      |              ^

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