Compilare: main.cpp: In function 'int main()': main.cpp:71:8: warning: this 'for' clause does not guard... [-Wmisleading-indentation] for ( it = v3[i].begin() ; it != v3[i].end() ; it ++ ) ^~~ main.cpp:73:13: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'for' g << '\n'; ^