Compilare: user.cpp: In function ‘void solve()’: user.cpp:17:21: warning: variable ‘nr’ set but not used [-Wunused-but-set-variable] int i, vf = -1, nr; ^ user.cpp:19:32: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%d %d", &N, &K); ^ user.cpp:25:24: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%s", v); ^