How to replace the 3rd column element of a matrix by comparing 1st and 2nd column of another matrix?

I have a matrix

A =

     1     2     5
     1     3     5
     1     4     5
     1     5     6
     2     3     6
     2     4     7
     3     4     7
     3     5     7
     4     5     7
and

B=

       1     2     3
       1     3     4
       1     4     5
       1     5     6
       2     3     4
       2     4     5
       3     4     5
       3     5     6
       4     5     6

i want to compare 1st and 2nd column and replace the element of 3rd column of B

for example,

in A when 1st and 2nd column is

[1 2]  in 3rd column its corresponding value is 5

so i want to replace B's 3rd column whenever in 1st and 2nd column are 1 2

same way when [1 3] it's value will be updated in B in same format.

please help me...

with regard

Suchismita

Answer 1

[Walter Roberson]

Have a look at ismember(V,B(:,1:2),'row')

[suchismita]

thank u so much....

[suchismita]

I was doing this way and was getting error,

[lo,ii] = ismember(B(:,1:2),A(:,1:2)
out = B;
out(lo,3) = A(ii(lo),3)

now i know where was the error...thank u once again