Compilare: user.cpp: In function ‘void inserare(char*)’: user.cpp:17: warning: comparison between signed and unsigned integer expressions user.cpp:18: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘void stergere(char*)’: user.cpp:32: warning: comparison between signed and unsigned integer expressions user.cpp:33: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘void numar_aparitii(char*)’: user.cpp:43: warning: comparison between signed and unsigned integer expressions user.cpp:44: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘void prefix(char*)’: user.cpp:55: warning: comparison between signed and unsigned integer expressions user.cpp:56: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int main()’: user.cpp:76: warning: format ‘%s’ expects type ‘char*’, but argument 3 has type ‘char (*)[21]’ user.cpp:88: warning: format ‘%s’ expects type ‘char*’, but argument 3 has type ‘char (*)[21]’ user.cpp:73: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:74: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:76: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:88: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result