foo.cc: In function 'int main()':
foo.cc:6:11: warning: right operand of comma operator has no effect [-Wunused-value]
    6 |  cin>>a,b,c,d;
      |           ^
foo.cc:6:13: warning: right operand of comma operator has no effect [-Wunused-value]
    6 |  cin>>a,b,c,d;
      |             ^
foo.cc:6:14: warning: right operand of comma operator has no effect [-Wunused-value]
    6 |  cin>>a,b,c,d;
      |              ^
foo.cc:7:17: warning: 'b' is used uninitialized in this function [-Wuninitialized]
    7 |  cout<<0.1*a+0.2*b+0.2*c+0.5*d<<endl;
      |              ~~~^~
foo.cc:7:23: warning: 'c' is used uninitialized in this function [-Wuninitialized]
    7 |  cout<<0.1*a+0.2*b+0.2*c+0.5*d<<endl;
      |                    ~~~^~
foo.cc:7:29: warning: 'd' is used uninitialized in this function [-Wuninitialized]
    7 |  cout<<0.1*a+0.2*b+0.2*c+0.5*d<<endl;
      |                          ~~~^~

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