Compilare: user.cpp: In function ‘int main()’: user.cpp:45:45: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<v[k].size();j++) ^ user.cpp:61:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v[0].size();i++) ^ user.cpp:12:14: warning: unused variable ‘x’ [-Wunused-variable] int nr=0,x,n=strlen(c),k=0,ms=1,nrnr=0; ^ user.cpp:11:12: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(c); ^ /tmp/cc0yWAcm.o: In function `main': user.cpp:(.text.startup+0x69): warning: the `gets' function is dangerous and should not be used.