Compilare: user.cpp: In function ‘int main()’: user.cpp:28:30: warning: operation on ‘x’ may be undefined [-Wsequence-point] v[++x]=v[x-1]; ^ user.cpp:19:9: warning: unused variable ‘i’ [-Wunused-variable] int i,j,k,x=1; ^ user.cpp:19:11: warning: unused variable ‘j’ [-Wunused-variable] int i,j,k,x=1; ^ user.cpp:19:13: warning: unused variable ‘k’ [-Wunused-variable] int i,j,k,x=1; ^