foo.cc: In function 'int main()':
foo.cc:7:13: warning: comparison with string literal results in unspecified behavior [-Waddress]
    7 |         if(x=="6")
      |            ~^~~~~
foo.cc:7:13: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
foo.cc:5:15: warning: unused variable 'sum' [-Wunused-variable]
    5 |         int x,sum=0;
      |               ^~~

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