foo.cc: In function 'int main()':
foo.cc:7:14: warning: right operand of comma operator has no effect [-Wunused-value]
    7 |     cin>>a,b,c,d;
      |              ^
foo.cc:7:16: warning: right operand of comma operator has no effect [-Wunused-value]
    7 |     cin>>a,b,c,d;
      |                ^
foo.cc:7:17: warning: right operand of comma operator has no effect [-Wunused-value]
    7 |     cin>>a,b,c,d;
      |                 ^
foo.cc:8:14: warning: 'b' is used uninitialized [-Wuninitialized]
    8 |     n=a*0.1+b*0.2+c*0.2+d*0.5;
      |             ~^~~~
foo.cc:5:11: note: 'b' was declared here
    5 |     int a,b,c,d;
      |           ^
foo.cc:8:20: warning: 'c' is used uninitialized [-Wuninitialized]
    8 |     n=a*0.1+b*0.2+c*0.2+d*0.5;
      |                   ~^~~~
foo.cc:5:13: note: 'c' was declared here
    5 |     int a,b,c,d;
      |             ^
foo.cc:8:26: warning: 'd' is used uninitialized [-Wuninitialized]
    8 |     n=a*0.1+b*0.2+c*0.2+d*0.5;
      |                         ~^~~~
foo.cc:5:15: note: 'd' was declared here
    5 |     int a,b,c,d;
      |               ^

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