Eroare de compilare: user.cpp: In function ‘void open_files()’: user.cpp:14: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:15: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp: In function ‘void read()’: user.cpp:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘int search(unsigned int)’: user.cpp:55: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘long long int solve_subseq(int)’: user.cpp:65: error: ‘memset’ was not declared in this scope user.cpp: In function ‘void write()’: user.cpp:88: warning: format ‘%ld’ expects type ‘long int’, but argument 2 has type ‘long long int’