Compilare: user.cpp: In function ‘int main()’: user.cpp:17:27: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(a + 1, MAXN, fi); ^ user.cpp:18:27: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(b + 1, MAXN, fi); ^