foo.cc:11:7: error: stray '\357' in program
   a+=x；
       ^
foo.cc:11:8: error: stray '\274' in program
   a+=x；
        ^
foo.cc:11:9: error: stray '\233' in program
   a+=x；
         ^
foo.cc: In function 'int main()':
foo.cc:12:3: error: expected ';' before 'i'
   i++;
   ^

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