foo.cc: In function 'int main()':
foo.cc:7:9: warning: 'a' is used uninitialized in this function [-Wuninitialized]
    7 | cout<<(a+b+c)<<endl;
      |        ~^~
foo.cc:7:9: warning: 'b' is used uninitialized in this function [-Wuninitialized]
foo.cc:7:13: warning: 'c' is used uninitialized in this function [-Wuninitialized]
    7 | cout<<(a+b+c)<<endl;
      |             ^

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