Compilare: user.cpp: In function ‘void readf()’: user.cpp:36:34: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d%d\n", &n, &k); ^ user.cpp:39:28: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(buf, 32, fin); ^ user.cpp: In function ‘int main()’: user.cpp:149:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen(_fout, "w", stdout); ^