foo.cc: In function 'int main()':
foo.cc:5:17: warning: 'a' is used uninitialized [-Wuninitialized]
    5 |         cout<<a+b<<endl;
      |                 ^
foo.cc:4:15: note: 'a' was declared here
    4 |         int b,a;
      |               ^
foo.cc:5:17: warning: 'b' is used uninitialized [-Wuninitialized]
    5 |         cout<<a+b<<endl;
      |                 ^
foo.cc:4:13: note: 'b' was declared here
    4 |         int b,a;
      |             ^

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