skyscraper.cpp: In function 'void setIn(std::string)':
skyscraper.cpp:7:31: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
7 | void setIn(string s) { freopen(s.c_str(),"r",stdin); }
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~
skyscraper.cpp: In function 'void setOut(std::string)':
skyscraper.cpp:8:32: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
8 | void setOut(string s) { freopen(s.c_str(),"w",stdout); }
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
skyscraper.cpp: In function 'int main()':
skyscraper.cpp:4:53: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
4 | #define file if (fopen("input.txt", "r")) { freopen("input.txt", "r", stdin); freopen("output.txt", "w", stdout); }
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
skyscraper.cpp:20:5: note: in expansion of macro 'file'
20 | file;
| ^~~~
skyscraper.cpp:4:87: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
4 | #define file if (fopen("input.txt", "r")) { freopen("input.txt", "r", stdin); freopen("output.txt", "w", stdout); }
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
skyscraper.cpp:20:5: note: in expansion of macro 'file'
20 | file;
| ^~~~