Ai?

I was wondering how i would go about and make an AI that actually guesses a number that i pick by whether i say "Too high" or "Too low".
Here is an example of code from a guessing game.

Code:

---

// Guess My Number
// The classic number guessing game

#include <iostream>
#include <cstdlib>
#include <ctime>

using namespace std;

int main()
{
        srand(time(0)); // seed random number generator

        int theNumber = rand() % 100 + 1; // random number between 1 and 100
        int guess= rand() % 100 + 1;//Computer guesses number between 1 and 100
        int tries = 0;
   
        cout << "\tWelcome to Guess My Number\n\n";

        do
        {
                cout << "Enter a guess: "<<guess;
                ++tries;

                if (guess > theNumber)
                        cout << "Too high!\n\n";

                if (guess < theNumber)
                        cout << "Too low!\n\n";

        } while (guess != theNumber);

        cout << "\nThat's it! You got it in " << tries << " guesses!\n";
       
        system("pause");

    return 0;
}

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Have the AI guese by generating random numbers. After each guese ajust the min or max random number values.

So you want to make a game that's impossible to win? :p

Code:

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int guess= rand() % 100 + 1;//Computer guesses number between 1 and 100

---

Like this:

Code:

---

int maxVal = 100;
int minVal = 1;

do{
  guess= rand() % maxVal + minVal;  // This has to be in the loop.

  cout << "Enter a guess: "<<guess;
  ++tries;

  if (guess > theNumber) {
    cout << "Too high!\n\n";
    maxVal = guess - minVal;
    }
  else if (guess < theNumber) { // Else if cause there is no point in checking both.
    cout << "Too low!\n\n";
    minVal = guess;
    maxVal = maxVal - minVal;
    }
} while (guess != theNumber);

---

My math appears to be a little messed up with the too low, but you get the idea.

I think the OP is talking about a program where the user thinks of a number and the AI tries to guese it, something like this:

Quote:

---

Welcome to the guessing game! Think of a number and I will guess it.
I guese 10
is it (h)igher or (l)ower?
h
I guese 20
...

---

pseudocode

Code:

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while(wrong)
{
guess = (min+max)/2
if (too_high) max = guess-1
else if (too_low) min = guess+1
else you guessed right
}

---

I was going to suggest a binary search, but Daryl beat me to it.