foo.cc: In function 'int main()':
foo.cc:5:17: warning: variable 'e' set but not used [-Wunused-but-set-variable]
    5 |         int a,w,e,r,s;
      |                 ^
foo.cc:5:19: warning: variable 'r' set but not used [-Wunused-but-set-variable]
    5 |         int a,w,e,r,s;
      |                   ^

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