Compilare: user.cpp: In function ‘void write()’: user.cpp:148:52: warning: array subscript has type ‘char’ [-Wchar-subscripts] fprintf(stdout, "%d", answer[result[val][j]]); ^ user.cpp:152:52: warning: array subscript has type ‘char’ [-Wchar-subscripts] fprintf(stdout, "%d", answer[result[j][val]]); ^ user.cpp: In function ‘int main()’: user.cpp:163:32: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%d %d", &task, &N); ^ user.cpp:166:28: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%d", &val); ^ user.cpp:180:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("magic.out", "w", stdout); ^