Use a variable as a counter. E.g., suppose the variable name was guesses. Start with guesses=0 and then do guesses=guesses+1 for each guess. I.e.,
guesses = 0;
value = whatever;
while( true )
% insert code for user to make a guess
guess = guess + 1;
% insert check to see if guess is equal to value. If so, break out of the loop
end
