bit-flip error: (a1)b)+a2)b2)(H)H)2+) →(a)b)+a2)b)2)(n|H)2+H) After parity-check measurement with QND =(aiBi +ai bw )o)laee), ae) ,+ 2H2H bir ))oy ae ge laeAfter parity-check measurement with QND： 1 1 2 2 1 1 2 2 ( )( ) ( )( ) a b a b a b a b a b a b H H V V a b a b V H H V + +  + + 1 1 1 1 2 2 2 2 ( ) 0 ( ) 0 i i H H V V a b i i H H V V a b a b a b e e a b a b e e         + + + +  + + + +   + + + bit-flip error：