Compilare: user.cpp: In function ‘int cbin(int, int, int)’: user.cpp:23:25: warning: variable ‘prev’ set but not used [-Wunused-but-set-variable] int m, first, last, prev, ans; ^ user.cpp: In function ‘int main()’: user.cpp:56:23: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fi,"%d",&n); ^ user.cpp:58:34: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fi,"%d",&v[i].val); ^