if the corresponding nodes in the two traversal have different data values , then they are not mirrors of each other .
if ( root1 . data != root2 . data ) : NEW_LINE INDENT return " No " NEW_LINE DEDENT st1 . append ( root1 ) NEW_LINE st2 . append ( root2 ) NEW_LINE root1 = root1 . left NEW_LINE root2 = root2 . right NEW_LINE