Eroare de compilare: user.cpp: In function ‘int div(char*)’: user.cpp:26:21: error: ‘strlen’ was not declared in this scope int aux, z=strlen(x); ^ user.cpp:30:8: warning: converting to non-pointer type ‘char’ from NULL [-Wconversion-null] x[z]=NULL; ^ user.cpp:37:1: warning: no return statement in function returning non-void [-Wreturn-type] } ^ user.cpp: In function ‘int main()’: user.cpp:48:31: error: ‘strlen’ was not declared in this scope switch(rest(s_cif(S,strlen(S)-1))) { ^