TicTacToe is cheating - objective-c

I've created a TTT game. However I'm having trouble with the AI taking spots. How do I avoid this from happening so that in the chooseCellRow:Col method it only returns a random spot that has not already been selected by either player?
- (void) chooseCellRow:(NSInteger)row Col:(NSInteger)col
{
//pick random spot for computer's turn
row = random()%2;
col = random()%2;
if (row == 0 && col == 0) {
[but00 setTitle:#"X" forState:0];
}
else if (row == 0 && col == 1) {
[but01 setTitle:#"X" forState:0];
}
else if (row == 0 && col == 2) {
[but02 setTitle:#"X" forState:0];
}
else if (row == 1 && col == 0) {
[but10 setTitle:#"X" forState:0];
}
else if (row == 1 && col == 1) {
[but11 setTitle:#"X" forState:0];
}
else if (row == 1 && col == 2) {
[but12 setTitle:#"X" forState:0];
}
else if (row == 2 && col == 0) {
[but20 setTitle:#"X" forState:0];
}
else if (row == 2 && col == 1) {
[but21 setTitle:#"X" forState:0];
}
else if (row == 2 && col == 2) {
[but22 setTitle:#"X" forState:0];
}
}

Cheating is a moral concept, one which doesn't apply to the computer since it's doing exactly what you've told it to do. However, you could prevent this by simply choosing again if the cell is already occupied, pseudo-code:
row = random() % 3;
col = random() % 3;
while cell[row][col] != empty: # Add your REAL detection code here.
row = random() % 3;
col = random() % 3;
You'll also notice that the above code stops you from cheating as well. Shame on you for only allowing the computer to choose four of the nine possibilities :-)
Applying % 2 to a number will give you 0 or 1, you need to use % 3 to allow for 2 as well.
Based on your comments that you have a cell array which contains the character occupying that cell, the code to continuse until you find a blank cell would be along the lines of:
do {
row = random() % 3;
col = random() % 3;
} while (cell[row][col] != ' ');

One easy way would be to keep a list of unused positions and choose from that list. When either player moves, remove the position they choose from the list.
Another, even simpler but less efficient way is to have it choose any position, but try again if the spot it picks is already occupied.

Related

Create a euphonious word

All the letters of the English alphabet are divided into vowels and consonants.
A word is considered euphonious if it doesn't have three or more vowels or consonants in a row.
My goal is to create euphonious words from the discordant ones and output the minimum number of characters needed to create a euphonious word from a given word.
Examples:
Input:
schedule
Output:
1
Input:
biiiiig
Output:
2
Code
fun main() {
val word = readLine()!!.toMutableList()
checkWord(word)
}
fun isVowel(c: Char): Boolean {
val vowels = listOf('a', 'e', 'i', 'o', 'u', 'y')
return c in vowels
}
fun checkWord(word: MutableList<Char>){
var counter = 0
for (number in 0 .. word.size - 2) {
if (isVowel(word[number]) && isVowel(word[number + 1]) && isVowel(word[number + 2])) {
counter++
word.add(number + 2, 'b')
// println(word)
}
if (!isVowel(word[number]) && !isVowel(word[number + 1]) && !isVowel(word[number + 2])) {
counter++
word.add(number + 2, 'a')
// println(word)
}
}
println(counter)
}
My code is working for those examples but not for a case like eeeeeeeeeeeeeeeee where the output is supposed to be 8 but my counter is 6.
Since the list is growing as you iterate, your for loop never reaches the end of the list. Your code can be fixed by replacing
for (number in 0 .. word.size - 2) {
with
var number = -1
while (++number < word.size - 1) {
so it checks the current list size on each iteration.
I want to point out however that it is unnecessary to use a MutableList and keep enlarging it since you don't use the "fixed" euphonious list afterwards. It is also unnecessary to repeatedly search neighbors on each iteration. You can just count as you go.
fun checkWord (word: String) {
var count = 0
var currentTypeCount = 0
var lastTypeVowel = true
for (c in word) {
if (isVowel(c) == lastTypeVowel) {
if (++currentTypeCount == 3) {
count++
currentTypeCount = 1
}
} else {
lastTypeVowel = !lastTypeVowel
currentTypeCount = 1
}
}
println(count)
}
Let's analyze the modifications of your word:
eebeeeeeeeeeeeeeee
eebeebeeeeeeeeeeeee
eebeebeebeeeeeeeeeee
eebeebeebeebeeeeeeeee
eebeebeebeebeebeeeeeee
eebeebeebeebeebeebeeeee
eebeebeebeebeebeebeebeee
eebeebeebeebeebeebeebeebe
Your last 2 modification take place on the letters with index, which is bigger than your word's original length. That happens because for loop iterations number is dependent on your word's original length.
I recommend you to use while loop, as its condition is always recalculated and word.size will be updated there
var i = 0
while (i + 2 < word.size) {
// the same logic
i++
}

Move selection sequentially in NSCollectionView

By default selection in NSCollectionView get moved by arrow keys within one row (or column).
How to make selection move sequentially, like items arranged by index?
Screenshot from developer.apple.com
I have asked same question to Apple Developer Technical Support, after checked they said "Our engineers have reviewed your request and have determined that this would be best handled as a bug report.". I submitted bug report to Apple's radar. So far no response.
I decided to implement my own solution. Subclass your NSCollectionView and override keyDown event.
Swift 4
override func keyDown(with event: NSEvent) {
if event.modifierFlags.rawValue == 10617090 {
return
}
if event.isARepeat == true && event.keyCode != 123 && event.keyCode != 124 && event.keyCode != 125 && event.keyCode != 126 {
return
}
if event.keyCode == 123 || event.keyCode == 124 || event.keyCode == 125 || event.keyCode == 126 {
for index in self.selectionIndexes {
if event.keyCode == 124 && index < YOUR_DATASOURCE_ARRAY.count - 1 {
self.deselectItems(at: [NSIndexPath(forItem: index, inSection: 0) as IndexPath])
self.selectItems(at: [NSIndexPath(forItem: index + 1, inSection: 0) as IndexPath], scrollPosition: NSCollectionView.ScrollPosition.nearestHorizontalEdge)
return
}
if event.keyCode == 123 && index > 0 {
self.deselectItems(at: [NSIndexPath(forItem: index, inSection: 0) as IndexPath])
self.selectItems(at: [NSIndexPath(forItem: index - 1, inSection: 0) as IndexPath], scrollPosition: NSCollectionView.ScrollPosition.nearestHorizontalEdge)
return
}
}
}
super.keyDown(with: event)
}
This interrupts left and right arrow key inputs and move selection to previous/next cell. Since
"Allows Multiple Selection" has to be NO. Also disable modifier keys as like CMD or Control.
If you keep pressing right arrow, when selection arrives to last cell at right hand it jump one row down and keep moving or vice versa for left arrow.
Hope it helps.

Comparing multiple values at once using &&

I have this code:
if ((total == (total1 && total2 && total3)))
{
[scrollview.contentOffset = CGPointMake (0,0)];
}
here is what it's something like on button action:
if (sender.tag == 1)
{
total1 = 10;
}
if (sender.tag == 2)
{
total2 = 20;
}
if (sender.tag == 3)
{
total3 = 30;
}
I am trying to go back to the start page of the scroll view if the user clicked the three correct buttons (similar to a password key).
Does the logical operator && work well in Objective-C, and did I use it right?
if ((total == (total1 && total2 && total3)))
You cannot do that. You have to explicitly compare each separately.
if ((total == total1) && (total == total2) && (total == total3)))
But that leaves the question of how total can be equal to all the three simultaneously though.
In your code:
if ((total == (total1 && total2 && total3)))
{
[scrollview.contentOffset = CGPointMake (0,0)];
}
When the if expression is evaluated, (total1 && total2 && total3) is evaluated first. And that can be either YES or NO (true or false if you prefer), or (0 or 1).
So your code is equivalent to the following:
BOOL allVariablesAreNotZero = total1 && total2 && total3;
if (total == allVariablesAreNotZero)
{
[scrollview.contentOffset = CGPointMake (0,0)];
}
Edit after the question was better explained
Make your buttons perform the following action when pressed:
- (void)buttonClicked:(id)sender
{
UIButton *button = (UIButton *)sender;
buttonsCombination = buttonsCombination | (1 << button.tag);
}
Where buttonsCombination is an NSUInteger. Then use the following test to see if the buttons that were pressed are the correct ones (I am doing this with three buttons, but you guess the idea)
NSUInteger correctCombination = (1 << button1) | (1 << button2) | (1 << button3)
if (buttonsCombination == correctCombination) {
// The combination is correct
} else {
// The combination is incorrect
}
buttonsCombination = 0;
Finally, note that this works because there are enough bits in a NSUInteger for 30 buttons.
Here I used bitwise operators | and <<.
What your current code is essentially saying is "if total is 'true' and total1, total2, and total3 are also all nonzero or if total is zero and total1, total2, and total3 are also all zero, then do something".
The && you have there is doing a logical/boolean comparison. It treats its arguments as being either true or false, and returns true if both arguments evaluate to true and false in any other case. The == compares the value of total with the true or false value that was obtained from your && expressions. That is probably not what you want here.
It seems like probably what you want to be saying is "if total is equal to the sum of total1, total2, and total3, then do something". Assuming this is the case, you would do:
if (total == (total1 + total2 + total3)) {
[scrollview.contentOffset = CGPointMake (0,0)];
}
Trying to determine what you mean by your comment on two other answers "i tried it but it executes the codes when i started to run the app" maybe this is what you're trying to achieve:
/* all in your button handler */
switch(sender.tag)
{
case 1:
total1 = 10;
break;
case 2:
total2 = 20;
break;
case 3:
total3 = 30;
break;
default:
break; // other buttons are ignored
}
// check it latest click means the total is now correct
if((total1 + total2 + total3) == total)
{
[scrollview.contentOffset = CGPointMake (0,0)];
}
So you update any totalX's effected by the button click and then check the condition to reset the scrolling.

Why does the Objective-C Compiler return a "y" as a "0" but then skips over the "if input==0" section?

int side1test;
NSLog(#"Is your triangle setup as in an Angle-Side-Angle? (Use 1 for Yes and 0 for No.)");
scanf(" %i", &side1test);
Returns "0" when the user enters a "y." However,
if (side1test != 1 && side1test != 0){
NSLog(#"Please use a '1' for YES and '0' for NO.");
}
Then does not catch.
The program drops into my else clause, and outputs all the NSLogs, skipping the scanf() commands, taking each of them as "0." What is wrong here?
I'm not a c++ dev but from googling that function returns the number of valid matches. If it returns 0 you should assume invalid input. side1test has not been set which is why it's 0.
Your code should probably be:--
int side1test;
NSLog(#"Is your triangle setup as in an Angle-Side-Angle? (Use 1 for Yes and 0 for No.)");
int result = 0;
while (result==0)
{
result =scanf(" %i", &side1test);
}
if (side1test != 1 && side1test != 0){
NSLog(#"Please use a '1' for YES and '0' for NO.");
}

android lock password combinations

I just came across with this interesting question from my colleague. I'm trying now, but meanwhile I thought I could share it here.
With the password grid shown in the Android home screen, how many valid passwords are possible?
min password length: 4 max: 9 (correct me if I'm wrong)
Summary
The full combinations of 4 to 9 distinctive numbers, minus the combinations which include invalid "jump"s.
The Long Version
The rule for Android 3x3 password grid:
one point for once
cannot "jump" over a point
The author of the original post used Mathematica to generate all 985824 combinations.
Because there is no "jump", several pairs of consecutive points are invalid.
Delete all invalid combinations to reach the result.
The combinations for 4-to-9-point paths are respectively 1624, 7152, 26016, 72912, 140704, 140704.
The Original Post In Chinese
The reference is from guokr, a site alike Stack Exchange Skeptics in the form of blogs.
I know this question is old, but I answered it in another question (before finding this question) with a brute force approach in python, so adding it here for posterity:
pegs = {
1: {3:2, 7:4, 9:5},
2: {8:5},
3: {1:2, 7:5, 9:6},
4: {6:5},
5: {},
6: {4:5},
7: {1:4, 3:5, 9:8},
8: {2:5},
9: {1:5, 3:6, 7:8}
}
def next_steps(path):
return (n for n in range(1,10) if (not path or n not in path and
(n not in pegs[path[-1]]
or pegs[path[-1]][n] in path)))
def patterns(path, steps, verbose=False):
if steps == 0:
if verbose: print(path)
return 1
return sum(patterns(path+[n], steps-1) for n in next_steps(path))
So you can list all the # of patterns for any number of steps:
>>> [(steps, patterns([], steps)) for steps in range(1,10)]
[(1, 9),
(2, 56),
(3, 320),
(4, 1624),
(5, 7152),
(6, 26016),
(7, 72912),
(8, 140704),
(9, 140704)]
>>> sum(patterns([], steps) for steps in range(4,10))
389112
This is not the most efficient way of solving it because you could use reflections and only calculate a 4*corner + 4*mid-edge + 1*middle, e.g.:
>>> patterns([], 6) == 4*patterns([1], 5) + 4*patterns([2], 5) + patterns([5], 5)
True
I brute forced the answer with a recursive search and i found a bigger answer, 487272. The algorithm is simple: trying it all. I quoted it down here. I didn't found any error in my code (but I'm not very skilled with c++). Sorry for the grammatical error I'm not English.
#include <iostream>
#include <stdlib.h>
using namespace std;
int combo; //counter
void research(int Ipoints /*number of points already took*/, bool Icheck[9]/*points matrix*/,int Ilast/*last took point*/,
int Icomboval/*combination representation, only for printing purpose*/, int deep/*number of iteration, only for printing purpose*/)
{
// int numcall = 0; //DEBUG
for( int i=0; i<9; i++) //Controlling every free point in search of a valid way to contimue
if( Icheck[i] == false )
{
//Just for security, coping every variable in a new variable. I don't know how c++ works but I will make it works
int points = Ipoints;
int last = Ilast;
int comboval = Icomboval;
bool check[9];
for( int j=0; j<9; j++)
check[j] = Icheck[j];
int e1,e2;
int middle = -1;
e1=i; e2=last; //Ccontrolling duble jumps
if( e1 == 0 && e2 == 2 ) middle = 1;
if( e1 == 3 && e2 == 5 ) middle = 4;
if( e1 == 6 && e2 == 8 ) middle = 7;
if( e1 == 0 && e2 == 6 ) middle = 3;
if( e1 == 1 && e2 == 7 ) middle = 4;
if( e1 == 2 && e2 == 8 ) middle = 5;
if( e1 == 0 && e2 == 8 ) middle = 4;
if( e1 == 6 && e2 == 2 ) middle = 4;
e2=i; e1=last; // in both way
if( e1 == 0 && e2 == 2 ) middle = 1;
if( e1 == 3 && e2 == 5 ) middle = 4;
if( e1 == 6 && e2 == 8 ) middle = 7;
if( e1 == 0 && e2 == 6 ) middle = 3;
if( e1 == 1 && e2 == 7 ) middle = 4;
if( e1 == 2 && e2 == 8 ) middle = 5;
if( e1 == 0 && e2 == 8 ) middle = 4;
if( e1 == 6 && e2 == 2 ) middle = 4;
if((middle != -1) && !(check[middle])) {
check[middle] = true;
points++; //adding middle points
comboval *= 10;
comboval += middle;
}
check[i] = true;
points++; // get the point
comboval*=10;
comboval += i+1;
if(points > 3)
{
combo++; // every iteration over tree points is a valid combo
// If you want to see they all, beware because printing they all is truly slow:
// cout << "Combination n. " << combo << " found: " << comboval << " , points " << points << " with " << deep << " iterations\n";
}
if(points > 9) //Just for sure, emergency shutdown,
{ exit(1); }
research(points,check,i,comboval,deep+1); /*Recursive, here is the true program!*/
// numcall++; //DEBUG
}
// cout << "Ended " << deep << " , with " << numcall << " subs called\n"; // Only for debug purposes,remove with all the //DEBUG thing
}
int main ()
{
combo = 0; //no initial knows combo
bool checkerboard[9];
for( int i=0; i<9; i++) checkerboard[i]=false; //blank initial pattern
research(0/*no point taken*/,checkerboard,-1/*just a useless value*/,0/*blank combo*/,1/*it's the firs iteration*/); //let's search!
cout << "\n" ;
cout << "And the answer is ... " << combo << "\n"; //out
char ans='\0';
while(ans=='\0')
{ //just waiting
cin >> ans;
}
return 0;
}
i just run a python code to get possible combinations
i got 985824 possibilities
from itertools import permutations
numbers = "123456789"
total_combos = list(permutations(numbers,4))+list(permutations(numbers,5))+list(permutations(numbers,6))+list(permutations(numbers,7))+list(permutations(numbers,8))+list(permutations(numbers,9))
print(len(total_combos))
(No of Points- Valid patterns)
(4 - 746)
(5 - 3268)
(6 - 11132)
(7 - 27176)
(8 - 42432)
(9 - 32256)
Total of 117010 valid Patterns are possible