Eroare de compilare: user.cpp: In function ‘int main()’: user.cpp:14: error: ‘strlen’ was not declared in this scope user.cpp:18: error: ‘strchr’ was not declared in this scope user.cpp:19: error: ‘strchr’ was not declared in this scope user.cpp:22: error: ‘strncpy’ was not declared in this scope user.cpp:23: error: ‘atoi’ was not declared in this scope user.cpp:24: error: ‘strcpy’ was not declared in this scope user.cpp:28: error: ‘strlen’ was not declared in this scope user.cpp:31: error: ‘strchr’ was not declared in this scope user.cpp:36: error: ‘strncpy’ was not declared in this scope user.cpp:39: error: ‘strstr’ was not declared in this scope user.cpp:50: error: ‘atoi’ was not declared in this scope user.cpp:51: error: ‘strcpy’ was not declared in this scope user.cpp:58: error: ‘atoi’ was not declared in this scope user.cpp:59: error: ‘strcpy’ was not declared in this scope user.cpp:63: error: ‘strlen’ was not declared in this scope user.cpp:69: error: ‘strcmp’ was not declared in this scope user.cpp:72: error: ‘strcpy’ was not declared in this scope user.cpp:11: warning: unused variable ‘z’