foo.cc:12:19: error: stray '\357' in program
   if(s[i]=='W')a++；
                   ^
foo.cc:12:20: error: stray '\274' in program
   if(s[i]=='W')a++；
                    ^
foo.cc:12:21: error: stray '\233' in program
   if(s[i]=='W')a++；
                     ^
foo.cc: In function 'int main()':
foo.cc:10:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<s.size();i++){
              ~^~~~~~~~~
foo.cc:13:3: error: expected ';' before 'else'
   else b++;
   ^~~~
foo.cc:21:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<s.size();i++){
              ~^~~~~~~~~

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