Compilare: main.cpp: In function 'int main()': main.cpp:48:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(vf[j] >= cif[j].size()) ~~~~~~^~~~~~~~~~~~~~~~ main.cpp:46:9: warning: unused variable 'ans' [-Wunused-variable] int ans = n, c = -1; ^~~ main.cpp:46:18: warning: unused variable 'c' [-Wunused-variable] int ans = n, c = -1; ^ main.cpp:61:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < cif[j].size(); i++) { ~~^~~~~~~~~~~~~~~