Compilare: user.cpp: In function ‘int main()’: user.cpp:10:21: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(a+1,N,fin); ^ user.cpp:11:21: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(b+1,N,fin); ^