我有数组数组，想要消除两面性。我怎么能这样做
<__NSArrayM 0x9175640>(
<__NSArrayI 0x919ec80>(
http://scontent-b.cdninstagram.com/hphotos-xfp1/outbound-distilleryimage2/t0.0-17/OBPTH/dccd6b4cb15211e3aeb912af24c9b212_5.jpg,
47738394,
evdokia_bach,
Evdokia Bach,
https://instagramimages-a.akamaihd.net/profiles/profile_47738394_75sq_1388023560.jpg
)
,
<__NSArrayI 0x919eca0>(
http://scontent-b.cdninstagram.com/hphotos-xpf1/outbound-distilleryimage10/t0.0-17/OBPTH/e27402bab15011e39584123223ad70da_5.jpg,
47799994,
allen,
allen warden,
https://instagramimages-a.akamaihd.net/profiles/profile_47738394_75sq_1388023560.jpg
)
,
<__NSArrayI 0x919ecc0>(
http://scontent-a.cdninstagram.com/hphotos-xaf1/outbound-distilleryimage6/t0.0-17/OBPTH/5794c4e0b15011e397e2122466b7dba2_5.jpg,
47738394,
evdokia_bach,
Evdokia Bach,
https://instagramimages-a.akamaihd.net/profiles/profile_47738394_75sq_1388023560.jpg
)
,
<__NSArrayI 0x919ece0>(
http://scontent-b.cdninstagram.com/hphotos-xpf1/outbound-distilleryimage11/t0.0-17/OBPTH/0f0916eab15011e3942d12c36745260f_5.jpg,
47738394,
evdokia_bach,
Evdokia Bach,
https://instagramimages-a.akamaihd.net/profiles/profile_47738394_75sq_1388023560.jpg
)
)
)
我只想要唯一的数组我该怎么做？