Compilare: main.cpp: In function 'int sel(int*, int, int, int)': main.cpp:89:1: warning: control reaches end of non-void function [-Wreturn-type] } ^ main.cpp: In function 'int main()': main.cpp:93:34: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("sdo.out","w",stdout); ^ main.cpp: In constructor 'instream::instream(const char*)': main.cpp:17:40: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fread(buffer,SIZE,1,input_file); ^ main.cpp: In member function 'void instream::advance()': main.cpp:43:44: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fread(buffer,SIZE,1,input_file); ^