foo.cc:18:30: error: stray '\357' in program
      if (a[i] >= k && a[i] <w）
                              ^
foo.cc:18:31: error: stray '\274' in program
      if (a[i] >= k && a[i] <w）
                               ^
foo.cc:18:32: error: stray '\211' in program
      if (a[i] >= k && a[i] <w）
                                ^
foo.cc: In function 'int main()':
foo.cc:18:10: warning: init-statement in selection statements only available with -std=c++1z or -std=gnu++1z
      if (a[i] >= k && a[i] <w）
          ^
foo.cc:19:6: error: expected ';' before 'cnt'
      cnt++;
      ^~~
foo.cc:18:20: warning: statement has no effect [-Wunused-value]
      if (a[i] >= k && a[i] <w）
          ~~~~~~~~~~^~~~~~~~~~
foo.cc:20:15: error: expected ')' before ';' token
    cout << cnt;
               ^

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