Compilare: user.cpp: In function ‘int main()’: user.cpp:13:20: warning: format ‘%s’ expects argument of type ‘char*’, but argument 3 has type ‘char (*)[1000001]’ [-Wformat=] fscanf(f, "%s", &s); ^ user.cpp:19:45: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (s[i] > s[i + 1] && i < strlen(s) - 1) ^ user.cpp:23:19: warning: NULL used in arithmetic [-Wpointer-arith] if (s[i + 1] == NULL) ^ user.cpp:12:32: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%lld %lld", &N, &X); ^ user.cpp:13:21: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%s", &s); ^