foo.cc: In function 'int main()':
foo.cc:8:18: warning: 'b' is used uninitialized [-Wuninitialized]
    8 |         r=a*0.2+b*0.2+c*0.6;
      |                 ~^~~~
foo.cc:5:15: note: 'b' was declared here
    5 |         int a,b,c;
      |               ^

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