foo.cc: In function 'int main()':
foo.cc:6:9: warning: 'a' is used uninitialized [-Wuninitialized]
    6 | cout<<a%b<<endl;
      |         ^
foo.cc:5:5: note: 'a' was declared here
    5 | int a,b;
      |     ^
foo.cc:6:9: warning: 'b' is used uninitialized [-Wuninitialized]
    6 | cout<<a%b<<endl;
      |         ^
foo.cc:5:7: note: 'b' was declared here
    5 | int a,b;
      |       ^

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