foo.cc:6:14: error: stray '\357' in program
     int n,a=1，b=1，c,d,e,i=1；
              ^
foo.cc:6:15: error: stray '\274' in program
     int n,a=1，b=1，c,d,e,i=1；
               ^
foo.cc:6:16: error: stray '\214' in program
     int n,a=1，b=1，c,d,e,i=1；
                ^
foo.cc:6:20: error: stray '\357' in program
     int n,a=1，b=1，c,d,e,i=1；
                    ^
foo.cc:6:21: error: stray '\274' in program
     int n,a=1，b=1，c,d,e,i=1；
                     ^
foo.cc:6:22: error: stray '\214' in program
     int n,a=1，b=1，c,d,e,i=1；
                      ^
foo.cc:6:32: error: stray '\357' in program
     int n,a=1，b=1，c,d,e,i=1；
                                ^
foo.cc:6:33: error: stray '\274' in program
     int n,a=1，b=1，c,d,e,i=1；
                                 ^
foo.cc:6:34: error: stray '\233' in program
     int n,a=1，b=1，c,d,e,i=1；
                                  ^
foo.cc:8:26: error: stray '\357' in program
  if n=1 cout<<1; return 0；‘
                          ^
foo.cc:8:27: error: stray '\274' in program
  if n=1 cout<<1; return 0；‘
                           ^
foo.cc:8:28: error: stray '\233' in program
  if n=1 cout<<1; return 0；‘
                            ^
foo.cc:8:29: error: stray '\342' in program
  if n=1 cout<<1; return 0；‘
                             ^
foo.cc:8:30: error: stray '\200' in program
  if n=1 cout<<1; return 0；‘
                              ^
foo.cc:8:31: error: stray '\230' in program
  if n=1 cout<<1; return 0；‘
                               ^
foo.cc: In function 'int main()':
foo.cc:6:17: error: expected ',' or ';' before 'b'
     int n,a=1，b=1，c,d,e,i=1；
                 ^
foo.cc:8:5: error: expected '(' before 'n'
  if n=1 cout<<1; return 0；‘
     ^
foo.cc:9:2: error: expected ';' before 'else'
  else while (i++;i<=n){
  ^~~~
foo.cc:9:2: error: 'else' without a previous 'if'
foo.cc:9:14: error: 'i' was not declared in this scope
  else while (i++;i<=n){
              ^
foo.cc:9:17: error: expected ')' before ';' token
  else while (i++;i<=n){
                 ^
foo.cc:9:18: error: 'i' was not declared in this scope
  else while (i++;i<=n){
                  ^
foo.cc:14:8: error: 'c' was not declared in this scope
  cout<<c;
        ^
foo.cc:6:11: warning: unused variable 'a' [-Wunused-variable]
     int n,a=1，b=1，c,d,e,i=1；
           ^

自豪的采用 HydroJudge 进行评测(github.com/hydro-dev/HydroJudge)