Compilare: user.cpp: In function ‘int main()’: user.cpp:26:15: warning: unused variable ‘l’ [-Wunused-variable] int n,M,k,l,mid,r,sol; ^ user.cpp:26:17: warning: unused variable ‘mid’ [-Wunused-variable] int n,M,k,l,mid,r,sol; ^~~ user.cpp:26:21: warning: unused variable ‘r’ [-Wunused-variable] int n,M,k,l,mid,r,sol; ^ user.cpp:26:23: warning: unused variable ‘sol’ [-Wunused-variable] int n,M,k,l,mid,r,sol; ^~~ user.cpp:27:22: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%i",&n); ^ user.cpp:30:32: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%i %i",&M,&k); ^