foo.cc: In function 'int main()':
foo.cc:7:11: warning: right operand of comma operator has no effect [-Wunused-value]
    7 |  cin>>a,b,c,d;
      |           ^
foo.cc:7:13: warning: right operand of comma operator has no effect [-Wunused-value]
    7 |  cin>>a,b,c,d;
      |             ^
foo.cc:7:14: warning: right operand of comma operator has no effect [-Wunused-value]
    7 |  cin>>a,b,c,d;
      |              ^
foo.cc:8:34: warning: 'b' is used uninitialized in this function [-Wuninitialized]
    8 |  cout<<setprecision(3)<<0.1*a+0.2*b+0.2*c+0.5*d;
      |                               ~~~^~
foo.cc:8:40: warning: 'c' is used uninitialized in this function [-Wuninitialized]
    8 |  cout<<setprecision(3)<<0.1*a+0.2*b+0.2*c+0.5*d;
      |                                     ~~~^~
foo.cc:8:46: warning: 'd' is used uninitialized in this function [-Wuninitialized]
    8 |  cout<<setprecision(3)<<0.1*a+0.2*b+0.2*c+0.5*d;
      |                                           ~~~^~

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