Compilare: user.cpp: In function ‘int main()’: user.cpp:42:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<v.size()&&v[i].x<=n;i++) ^ user.cpp:46:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=i+1;j<v.size()&&v[i].x==v[j].x;j++) ^ user.cpp:30:13: warning: unused variable ‘k’ [-Wunused-variable] int i,j,k,r,ok,nr=0,start,a,b,c,d; ^ user.cpp:30:15: warning: unused variable ‘r’ [-Wunused-variable] int i,j,k,r,ok,nr=0,start,a,b,c,d; ^ user.cpp:30:17: warning: unused variable ‘ok’ [-Wunused-variable] int i,j,k,r,ok,nr=0,start,a,b,c,d; ^ user.cpp:30:25: warning: unused variable ‘start’ [-Wunused-variable] int i,j,k,r,ok,nr=0,start,a,b,c,d; ^