foo.cc: In function 'bool check(std::__cxx11::string, std::__cxx11::string, std::__cxx11::string)':
foo.cc:10:4: error: 'ture' was not declared in this scope
  f=ture;
    ^~~~
foo.cc:10:4: note: suggested alternative: 'time'
  f=ture;
    ^~~~
    time
foo.cc: In function 'int main()':
foo.cc:23:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&n);
  ~~~~~^~~~~~~~~

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