Compilare: user.cpp: In function ‘void solve(char*, int)’: user.cpp:34: warning: unused variable ‘length_pos’ user.cpp: In function ‘int main()’: user.cpp:111: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp:112: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result user.cpp:115: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result