View Compilation Error

0_0_17277339_14628.cpp: In function 'int main()':
0_0_17277339_14628.cpp:17:50: error: 'xz' was not declared in this scope
   if ((x3-x0)*vx+(y3-y0)*vy+(z3-z0)*vz != 0 && !(xz==0&&xy==0&&xz==0))
                                                  ^
0_0_17277339_14628.cpp:17:57: error: 'xy' was not declared in this scope
   if ((x3-x0)*vx+(y3-y0)*vy+(z3-z0)*vz != 0 && !(xz==0&&xy==0&&xz==0))
                                                         ^