22. 已知直线l1:2x+2y−1=0l_{1}:2x+2y-1=0l1:2x+2y−1=0,l2:4x+ny+3=0l_{2}:4x+ny+3=0l2:4x+ny+3=0,l3:mx+6y+1=0l_{3}:mx+6y+1=0l3:mx+6y+1=0,若l1//l2l_{1}//l_{2}l1//l2且l1⊥l3l_{1}\bot l_{3}l1⊥l3,则m+nm+nm+n值为((( )))