Compilare: main.cpp: In function 'void back(long long int)': main.cpp:36:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(long long i = 0; i < v.size(); ++i) ~~^~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:55:5: warning: this 'for' clause does not guard... [-Wmisleading-indentation] for(long long i = 1; i <= 9; ++i) ^~~ main.cpp:58:2: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'for' if(a == 1000 && b == 210) ^~