Compilare: user.cpp: In function ‘int main()’: user.cpp:69:48: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j = 0; j < Ap1[S1[i] - 'a'].size (); j ++) ^ user.cpp:43:24: warning: unused variable ‘a’ [-Wunused-variable] int i, j, Ans = 0, a = 0, b = 0; ^ user.cpp:43:31: warning: unused variable ‘b’ [-Wunused-variable] int i, j, Ans = 0, a = 0, b = 0; ^