Compilare: user.cpp: In function ‘int main()’: user.cpp:68:29: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("rest.in","r",stdin); ^ user.cpp:69:31: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("rest.out","w",stdout); ^ user.cpp:70:33: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buffer,1,buffersize,stdin); l=0; ^ user.cpp:80:33: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buffer,1,buffersize,stdin); l=0; ^ user.cpp: In function ‘void read(int&)’: user.cpp:20:50: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] l=0; fread(buffer,1,buffersize,stdin); ^ user.cpp:27:50: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] l=0; fread(buffer,1,buffersize,stdin); ^ user.cpp: In function ‘pr cauta(std::vector<std::pair<int, int> >&, int)’: user.cpp:48:1: warning: control reaches end of non-void function [-Wreturn-type] } ^