Compilare: user.cpp: In function ‘void calc(int, int)’: user.cpp:22:25: warning: array subscript has type ‘char’ [-Wchar-subscripts] sv += v[s[i - k]]; ^ user.cpp: In function ‘int main()’: user.cpp:40:25: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(s, MAXL + 2, in); ^ user.cpp:41:23: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%d", &m); ^