foo.cc: In function 'int main()':
foo.cc:6:7: warning: 'a' is used uninitialized in this function [-Wuninitialized]
    6 |  sum=(a*0.2+b*0.2+c*0.6);
      |       ^
foo.cc:6:13: warning: 'b' is used uninitialized in this function [-Wuninitialized]
    6 |  sum=(a*0.2+b*0.2+c*0.6);
      |             ^
foo.cc:6:19: warning: 'c' is used uninitialized in this function [-Wuninitialized]
    6 |  sum=(a*0.2+b*0.2+c*0.6);
      |                   ^

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