foo.cc:11:12: error: stray '\357' in program
   11 |  while(j<=n）
      |            ^
foo.cc:11:13: error: stray '\274' in program
   11 |  while(j<=n）
      |             ^
foo.cc:11:14: error: stray '\211' in program
   11 |  while(j<=n）
      |              ^
foo.cc: In function 'int main()':
foo.cc:11:12: error: expected ')' before '{' token
   11 |  while(j<=n）
      |       ~    ^
      |            )
   12 |  {
      |  ~          
foo.cc:17:15: error: expected primary-expression before '<<' token
   17 |     cout<<sum><<endl;
      |               ^~

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