foo.cc:8:20: error: stray '\357' in program
    8 |  for(i=2;i<=n/2;i++；)
      |                    ^
foo.cc:8:21: error: stray '\274' in program
    8 |  for(i=2;i<=n/2;i++；)
      |                     ^
foo.cc:8:22: error: stray '\233' in program
    8 |  for(i=2;i<=n/2;i++；)
      |                      ^
foo.cc:21:9: error: stray '\357' in program
   21 |  for(i=N；i>=2;i--；)
      |         ^
foo.cc:21:10: error: stray '\274' in program
   21 |  for(i=N；i>=2;i--；)
      |          ^
foo.cc:21:11: error: stray '\233' in program
   21 |  for(i=N；i>=2;i--；)
      |           ^
foo.cc:21:20: error: stray '\357' in program
   21 |  for(i=N；i>=2;i--；)
      |                    ^
foo.cc:21:21: error: stray '\274' in program
   21 |  for(i=N；i>=2;i--；)
      |                     ^
foo.cc:21:22: error: stray '\233' in program
   21 |  for(i=N；i>=2;i--；)
      |                      ^
foo.cc: In function 'int main()':
foo.cc:21:9: error: expected ';' before 'i'
   21 |  for(i=N；i>=2;i--；)
      |         ^  ~
      |         ;
foo.cc:21:20: error: expected ';' before ')' token
   21 |  for(i=N；i>=2;i--；)
      |                    ^  ~
      |                    ;

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