foo.cc: In function 'int main()':
foo.cc:7:18: warning: right operand of comma operator has no effect [-Wunused-value]
    7 |         cin>>a,b,c,d;
      |                  ^
foo.cc:7:20: warning: right operand of comma operator has no effect [-Wunused-value]
    7 |         cin>>a,b,c,d;
      |                    ^
foo.cc:7:21: warning: right operand of comma operator has no effect [-Wunused-value]
    7 |         cin>>a,b,c,d;
      |                     ^
foo.cc:8:18: warning: 'b' is used uninitialized [-Wuninitialized]
    8 |         e=a*0.1+b*0.2+c*0.2+d*0.5;
      |                 ~^~~~
foo.cc:5:15: note: 'b' was declared here
    5 |         int a,b,c,d;
      |               ^
foo.cc:8:24: warning: 'c' is used uninitialized [-Wuninitialized]
    8 |         e=a*0.1+b*0.2+c*0.2+d*0.5;
      |                       ~^~~~
foo.cc:5:17: note: 'c' was declared here
    5 |         int a,b,c,d;
      |                 ^
foo.cc:8:30: warning: 'd' is used uninitialized [-Wuninitialized]
    8 |         e=a*0.1+b*0.2+c*0.2+d*0.5;
      |                             ~^~~~
foo.cc:5:19: note: 'd' was declared here
    5 |         int a,b,c,d;
      |                   ^

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