Compilare: user.cpp: In function ‘void citire()’: user.cpp:21:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<strlen(A);++i) ^ user.cpp:27:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<strlen(A);++i) ^ user.cpp:35:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<strlen(A);j++) ^ user.cpp:20:9: warning: unused variable ‘i’ [-Wunused-variable] int i=0; int a=0; ^