Compilare: user.cpp: In function ‘bool find()’: user.cpp:20:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<v[list].size();++i) ^ user.cpp: In function ‘int main()’: user.cpp:42:24: warning: format ‘%s’ expects argument of type ‘char*’, but argument 2 has type ‘char (*)[20]’ [-Wformat=] scanf("%s\n",&c); ^ user.cpp:54:24: warning: format ‘%s’ expects argument of type ‘char*’, but argument 2 has type ‘char (*)[20]’ [-Wformat=] scanf("%s\n",&c); ^