foo.cc: In function 'int main()':
foo.cc:6:5: warning: statement has no effect [-Wunused-value]
    6 |  a+b==x
      |  ~~~^~~
foo.cc:7:9: warning: 'x' is used uninitialized in this function [-Wuninitialized]
    7 |  ;cout<<x<<endl;
      |         ^

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