help needed to develop an algorithm -

hi need small develop algorithm.. if there algorithm existing please update me.

this want do.

i have 4 input text box , 1 out put text box. in input text box want give 4 characters. example a, a, a, b. output textbox should give me answer "a".

i want check entered character in input textbox , want display it.

sample input , output required (text1,text2,text3,text4 = output)

a,a,a,a = a,b,a,a = a,a,b,b = a,a,b,a = c,c,a,c = c 

this program writing in c# visual studio 2010 ultimate.. advise welcome....

thanks..

ok, i'll go tact; pseudo code. if can't turn real code, go hand textbook teacher , tell him you're not suited class.

define dictionary key 'char' , value integer each textbox    read character textbox    increment 1 dictionary value associated character find highest value in dictionary output associated key