How to push_back something into a 2D Vector - c++

I'm trying to code a Tic-Tac-Toe game and can't figure out how to push_back a '+' char whenever it's my turn.
So whenever a player types for example "Oben links" which basically means Top left I want the game to check for the correct input and place a '+' at the position the player picked. What I am doing though does not seem to work. Either it's not saving it or I'm using the wrong syntax.
int main() {
vector < vector <char> > spielbrett(3, vector<char>('3'));
bool gewonnen = true;
string feld;
while (gewonnen) {
cout << "Position waehlen, z. B. Oben links oder Mitte Mitte usw. " << endl;
for (int i = 0; i < 3; i++) {
for (int j = 0; j < 3; j++) {
cout << spielbrett[i][j] << " ";
if (j < 2) {
cout << " | ";
}
}
if (i < 2) {
cout << endl << " ------------ " << endl;
}
}
cout << endl << endl << endl;
cin >> feld;
if (feld == "Oben links") {
spielbrett[0].push_back('+');
}
else if (feld == "Oben mittig") {
}
else if (feld == "Oben rechts") {
}
else if (feld == "Mitte links") {
}
else if (feld == "Mitte mittig") {
}
else if (feld == "Mittig rechts") {
}
else if (feld == "Unten links") {
}
else if (feld == "Unten mittig") {
}
else if (feld == "Unten rechts") {
}
}
system("pause");
}

You do not want to use push_back here. Since the vector is already 3x3 thanks to
vector < vector <char> > spielbrett(3, vector<char>('3'));
All you need to do is access the positions directly. So if you want the top left corner then you want
spielbrett[0][0] = '+';
The bottom right would be
spielbrett[2][2] = '+';

Related

C++ Program leaving my for loop prematurely

I'm working on a little poker application and i've run into the first problem I just can't seem to comprehend.
while (allplayersGood != 1) { //round table till all decided
cout << "TOP OF WHILE LOOP";
for (int i = 0; i < PLAYER_COUNT; i++) { //for loop for decisions from non button or blinds
int player_decision = 1;
char choice;
if ((players[i].playerhand.card1.value != 'F') && (players[i].playerhand.card1.value != 'C')) {
if ((players[i].blind != 1 && players[i].blind != 2) && players[i].button != true) {
cout << "\n\n";
cout << " POT: " << playerTable->currentPot;
cout << "\n";
for (int i = 0; i < PLAYER_COUNT; i++) {
cout << "Player " << players[i].playernumber;
cout << " (" << players[i].chip_amount << ") ";
}
while (player_decision == 1) {
if (playerTable->currentBet > players[i].currentBet) {
cout << "\n\nPlayer " << players[i].playernumber << " ("; players[i].playerhand.printhand(); cout << ") " << "Type F for Fold, B for Call, R for Raise: ";
cin >> choice;
players[i].choice = choice;
if (choice == 'F') {
player_decision = 0;
players[i].fold();
}
if (choice == 'R') {
player_decision = 0;
players[i].bet(playerTable);
}
if (choice == 'B') {
player_decision = 0;
players[i].call(playerTable);
}
}
if ((playerTable->currentBet == players[i].currentBet) && player_decision != 0) { //big blind after round table
cout << "\n\nPlayer " << players[i].playernumber << " ("; players[i].playerhand.printhand(); cout << ") " << "Type C for Check, R for Raise: ";
cin >> choice;
players[i].choice = choice;
if (choice == 'B') {
player_decision = 0;
players[i].bet(playerTable);
}
if (choice == 'C') {
if (players[i].check(playerTable) == true) {
player_decision = 0;
}
}
}
}
}
else if (players[i].blind == 1 || players[i].blind == 2) {
if (players[i].blind == 1) {
players[i].chip_amount -= sblind;
playerTable->currentPot += sblind;
players[i].blind = 0;
players[i].currentBet = sblind;
}
if (players[i].blind == 2) {
players[i].chip_amount -= bblind;
playerTable->currentPot += bblind;
players[i].blind = 0;
players[i].currentBet = bblind;
}
}
}
}
for (int i = 0; i < PLAYER_COUNT; i++) { //seperate loop for button and blinds that were ignored in loop above
int player_decision = 1;
char choice;
if (players[i].button == true || players[i].blind == 1) { //button and small blind
cout << "\n\n";
cout << " POT: " << playerTable->currentPot;
cout << "\n";
for (int i = 0; i < PLAYER_COUNT; i++) {
cout << "Player " << players[i].playernumber;
cout << " (" << players[i].chip_amount << ") ";
}
while (player_decision == 1) {
cout << "\n\nPlayer " << players[i].playernumber << " ("; players[i].playerhand.printhand(); cout << ") " << "Type F for Fold, B for Call, R for Raise: ";
cin >> choice;
players[i].choice = choice;
if (choice == 'F') {
player_decision = 0;
players[i].fold();
}
if (choice == 'R') {
player_decision = 0;
players[i].bet(playerTable);
}
if (choice == 'B') {
player_decision = 0;
players[i].call(playerTable);
}
}
}
cout << i;
if (players[i].blind == 2) { //big blind
cout << "\n\n";
cout << " POT: " << playerTable->currentPot;
cout << "\n";
for (int i = 0; i < PLAYER_COUNT; i++) {
cout << "Player " << players[i].playernumber;
cout << " (" << players[i].chip_amount << ") ";
}
while (player_decision == 1) {
cout << "\n\nPlayer " << players[i].playernumber << " ("; players[i].playerhand.printhand(); cout << ") " << "C for Check, R for Raise: ";
cin >> choice;
players[i].choice = choice;
if (choice == 'C') {
if (players[i].check(playerTable) == true) {
player_decision = 0;
}
}
if (choice == 'R') {
player_decision = 0;
players[i].bet(playerTable);
}
}
}
}
int playersBetting = 0;
int playersGood = 0;
int playersChecked = 0;
int playersNot = 0;
for (int i = 0; i < PLAYER_COUNT; i++) {
if (players[i].playerhand.card1.value != 'F') {
playersBetting++;
if (players[i].currentBet == playerTable->currentBet) {
playersGood++;
}
}
}
for (int i = 0; i < PLAYER_COUNT; i++) {
if (players[i].playerhand.card1.value != 'F') {
if (players[i].isChecked == true) {
playersChecked++;
}
else {
playersNot++;
}
}
}
cout << playersBetting << playersGood;
if ((playersBetting == playersGood) || (playersNot == 0)) {
cout << "NEXT ROUND STARTED";
}
}
The issue is, during the second for loop with comment "seperate loop for button and blinds that were ignored in loop above" after the first if statement succeeds because players[0] has button equal to true, the player will make the terminal input as a decision, and the program will exit the for loop and go down to the end with the playersBetting and playersGood loops, then return back to the for loop at index 1 correctly.
I'm sorry if this is a little complicated to understand there is a lot of code that I probably didn't put into context very well, if you need any extra information please let me know.
Thank you.
You seem to have different loops inside one another. This is possible, but in that case, you need to use another loop variable (j instead of i), let me show you what happens:
for i ...
for j ...
This causes the following values to be taken for i and j:
i j
1 1
1 2
1 ...
1 n
2 1
2 2
2 ...
2 n
...
n 1
n 2
...
n n
... and here it stops.
If you keep using i in the inner loop, this is what you get:
i (outside loop) i (inside loop)
1 1
2 2 // indeed: changing i inside also changes i outside
... ...
n n
So you jump out of the outside loop, even after just having looped the inside loop one time.
I figured it out, it was unrelated to the actual loop and actually had to do with a value I changed upstream. Thank you for the few who tried to help with such little context haha
Have a good one

How to print a message only once in a loop

I am using for loops combined with if statements to read integers from a text file into a two-dimensional array.
This is my code:
for (int i = 0; i < MAX_ROWS;i++) {
for (int j = 0; j < MAX_COLUMNS; j++) {
inFile >> ArrB[i][j];
if (ArrB[i][j] == -1) {
bad = true;
cout << "The array does not have enough integers" << endl;
break;
}
else {
if (ArrB[i][j] < 1) {
invalidnum = true;
}
}
if (invalidnum = true) {
cout << *(*(ArrB + i) + j) << " ";
cout << "There is/are negative number(s) or zero(s) in the array imported from your text file." << endl;
}
}
}
This code will read in the first 6 integers (max_row * max_column) from a text file into ArrB.
If -1 exists in the first 6 integers, it will exit the loop and print out "The array does not have enough integers".
If there is no -1 in the first 6 integers, then it will check all 6 integers to see if there are any other negative numbers or zero.
If there are negative numbers or zero, I want it to still print out the array, then print out the error message (There is/are negative number(s) or zero(s) in the array imported from your text file) ONLY ONCE.
For example, this is my text file. As you can see, there is no -1 in the first 6 numbers, but there is a -7.
So, ideally, the result should be something like:
2 4 5 6 9 -7
There is/are negative number(s) or zero(s) in the array imported from your text file
But this is what I am getting if I run my code above:
-------------------------------------UPDATE--------------------------------------
Figured it out based on #ZedLepplin 's comment
Here is the code:
for (int i = 0; i < MAX_ROWS;i++) {
for (int j = 0; j < MAX_COLUMNS; j++) {
inFile >> ArrB[i][j];
if (ArrB[i][j] == -1) {
bad = true;
cout << "The array does not have enough integers" << endl;
break;
}
else {
if (ArrB[i][j] < 1) {
invalidnum = true;
}
}
cout << *(*(ArrB + i) + j) << " ";
}
}
if (invalidnum == true) {
cout << "There is/are negative number(s) or zero(s) in the array imported from your text file." << endl;
}
You could just set a counter, and put the message outside of the loop.
Something like :
int counter = 0;
for(int i = 0; i < MAX_ROWS ; i++) {
if(myVector[i] == -1) {
counter++;
}
else {
// Do normal stuff
}
}
if(counter > 0) {
cout << "The array contained " << counter << "negative values" << endl;
}
Ho, and I'd advise to avoid comparisons to "true". If myVar is a boolean alrady, I can just do if(myVar). No need to do if(myVar == true).
And doing if(myVar = true) is worse, as it sets myVar to true, regardless of its initial value. That's a common typo that can be hard to detect when proofreading code.
Edited version (to adapt to comments) :
bool earlyNegativeOneFound = false;
int otherNegativeCounter;
for(int i = 0; i < MAX_ROWS ; i++) {
if(i < 6 && myVector[i] == -1) {
earlyNegativeOneFound = true;
break;
}
else if(myVector[i] < 0) {
cout << myVector[i] << endl;
otherNegativeCounter++;
}
else {
// Do normal stuff
}
}
if(!earlyNegativeOneFound && otherNegativeCounter> 0) {
cout << "The array contained " << otherNegativeCounter << "negative values" << endl;
}
Put the conditional error message print after your for loop. Leave the cout for displaying the array number inside the for loop so it is output for every iteration of the loop.
for (int i = 0; i<MAX_ROWS;i++) {
for (int j = 0; j<MAX_COLUMNS; j++) {
inFile >> ArrB[i][j];
if (ArrB[i][j] == -1) {
bad = true;
cout << "The array does not have enough integers" << endl;
break;
}
else {
if (ArrB[i][j] < 1) {
invalidnum = true;
}
}
cout << * (*(ArrB + i) + j) << " ";
}
}
if (invalidnum = true) {
cout << "There is/are negative number(s) or zero(s) in the array imported from your text file." << endl;
}
I am not sure if this is what you meant
for (int i = 0; i < MAX_ROWS;i++) {
for (int j = 0; j < MAX_COLUMNS; j++) {
flag log = false;
inFile >> ArrB[i][j];
if (ArrB[i][j] == -1) {
bad = true;
cout << "The array does not have enough integers" << endl;
break;
}
else {
if (ArrB[i][j] < 1) {
invalidnum = true;
}
}
if (invalidnum = true) {
cout << *(*(ArrB + i) + j) << " ";
if(!flag)
{
cout << "There is/are negative number(s) or zero(s) in the array
imported from your text file." << endl;
flag = true;
}
}
}
}
Adding the flag boolean variable would allow the statement "there are negative numbers.." to be printed once.
Just store the message and print it where and when you want. Some psuedo-code:
std::string message;
for (int i = 0; i < N; ++i)
{
for (int j = 0; j< M; ++j)
{
if (smth)
{
message {"Your message"};
break; // note that after break,
// you are still in the outer loop
}
else if (smth else)
{
message {"Your message"};
}
}
// print it here
}
// or here, or wherever you want to

comparing two integers arrays in c++ string printing

I am trying to compare two arrays.where if it is true it needs to print the string.since it need to print only one time but the string is printing three times .where i have stored three values in both arrays.can you guys spot and tell me what is wrong.
for (int i = 0; i < n; i++)
{
if (l[i] == g[i])
{
cout << "equal" << endl;
}
else if (l[i] < g[i])
{
cout << "lesser" << endl;
}
else if (l[i] > g[i])
{
cout << "greater" << endl;
}
}
I'm guessing that you're trying to do a lexicographic comparison.
It should be obvious that if you want to print the message only once then you shouldn't put the print statements inside the loop.
The following code works how I think you want your code to work. The result of the comparison is stored in a variable result and that variable is examined only after the loop has finished. I use break because once you have found an item that is not equal there is no need to carry on the comparison.
int result = 0;
for (int i = 0; i < n; i++)
{
if (l[i] < g[i])
{
result = -1;
break;
}
else if (l[i] > g[i])
{
result = +1;
break;
}
}
if (result == 0)
cout << "equal" << endl;
else if (result < 0)
cout << "lesser" << endl;
else
cout << "greater" << endl;
You could simplify:
for (int i = 0; i < n; ++i)
{
const int l_value = l[i];
const int g_value = g[i];
if (l_value == g_value)
{
cout << "slot[" << i << "] is equal\n";
}
else
{
if (l_value < g_value)
{
cout << "slot[" << i << "] is less than\n";
}
else
{
cout << "slot[" << i << "] is greater than\n";
}
}
}
In order compare the entire array, you'll need to sort it first. The "less than" and "greater than" apply to a sorted array.

Removing and shifting remaining elements in an array C++

List.cpp (class definitions)
I have been working on code that is suppose to help familiarize with classes. My code currently has a function that displays a menu of options for the users. Option [1] is suppose to add a string, option [2] is suppose to remove a string from the list, option [3] prints the string list, option [4] exits. My option [1] seems to work okay as the user is able to input one string at a time but I am having a hard time with the removal of a string. The strings are currently stored in an array of 10 elements. I believe the function I wrote for the string removal is okay as I have debugged it and it seems successful, however, I am not seeing results on my console window.
My array is located in a private class in my class: string items[MAX_ITEMS]; along with another variable called: int totalItems;
The class is then called in my main function using a switch case:
//This code snippet below is located in a separate cpp file with main
cout << "Please enter the text you want to remove: " << endl;
cin >> userInput;
list1.remove(userInput);
////////////////////////////////////////////////////////////////////
//preprocessor directives
#include <iostream>
#include <string>
//header files
#include "list.h"
using namespace std;
List::List()
{
//clear array prior to starting (set everything to NULL)
for (int i = 0; i < MAX_ITEMS; i++)
{
items[i] = " ";
}
totalItems = 0;
}
//void List::init()
//{
// string items[MAX_ITEMS];
// totalItems = 0;
//}
bool List::insert(const string& data)
{
//verifies that string is not empty, not in the list, and not full
if (data.empty() == true || inList(data) == true || isFull() == true)
{
return false;
}
else
{
// items[isFull)] = data;
// totalItems++;
items[totalItems++] = data;
return true;
}
}
bool List::isEmpty() const
{
//runs through loop to verify array is empty
for (int i = 0; i < MAX_ITEMS; i++)
{
if (items[i].empty() != true)
{
return false;
}
}
return true;
}
//identifies whether the string is full or not
bool List::isFull() const
{
if (totalItems == MAX_ITEMS)
{
return true;
}
else
{
return false;
}
}
//identifies whether the string is already in the list or not
bool List::inList(const string& theList)
{
for (int i = 0; i < MAX_ITEMS; i++)
{
if (items[i] == theList)
{
return true;
}
}
return false;
}
bool List::remove(const string& data)
{
if (inList(data) == true || data.empty() == true)
{
return false;
}
for (int i = 0; i < MAX_ITEMS; i++)
{
if (items[i] == data)
{
items[i] == " ";
for (int j = i; j < MAX_ITEMS; j++)
{
items[j] = items[j + 1];
items[MAX_ITEMS - 1] == " ";
break;
}
}
}
totalItems--;
return true;
}
//prints list
void List::printList()
{
for (int i = 0; i < MAX_ITEMS; i++)
{
cout << i << items[i] << '\t';
}
}
list_test.cpp (main.cpp)
#include <iostream>
#include <string>
//header files
#include "list.h"
using namespace std;
//function prototypes
int showSelection();
int main()
{
List list1;
string userInput = "";
int userChoice;
// list1.init();
userChoice = showSelection();
while (userChoice != 4)
{
switch(userChoice)
{
case 1:
cout << "Please enter the text you want to add: " << endl;
cin >> userInput;
list1.insert(userInput);
/*if (list1.inList(userInput) == false)
{
cout << "Text is already entered in the list!" << endl;
}*/
if (list1.isFull() == true)
{
cout << "You have entered the MAXIMUM amount of elements!" << endl;
}
break;
case 2:
cout << "Please enter the text you want to remove: " << endl;
cin >> userInput;
list1.remove(userInput);
break;
case 3:
cout << "Printed list: " << endl;
list1.printList();
break;
}
userChoice = showSelection();
}
cout << "Goodbye. Please press enter to exit." << endl;
//TESTING PURPOSES FOR FUNCTIONS
cout << list1.insert(userInput) << endl;
cout << list1.isEmpty() << endl;
cout << list1.isFull() << endl;
cout << list1.inList(userInput) << endl;
return 0;
}
/* ===========================================
Name: showSelection
Desc: displays menu for user to choose options
for their inputted string(s).
Args: none
Retn: none
=========================================== */
int showSelection()
{
int userChoice;
bool exit = false;
while (exit == false)
{
cout << "\nTo select an option, please enter the corresponding number: " << endl;
cout << "[1] to add a string" << endl;
cout << "[2] to remove a string" << endl;
cout << "[3] to print a string" << endl;
cout << "[4] to exit" << endl << endl;
cin >> userChoice;
cout << "You entered option: " << userChoice << endl;
cout << '\n';
if (userChoice == 1 || userChoice == 2 || userChoice == 3 || userChoice == 4)
{
exit = true;
}
else
{
cout << "Invalid selection" << endl;
}
}`enter code here`
return userChoice;
}
Here is how you code should probably look:
bool List::remove(const string& data) {
// only check if the list is empty so you don't nececarily go through it
// you shoudn't ask here if the given string is in the list
// because you will search for it anyway just below
if (data.empty())
return false;
for (int i = 0; i < MAX_ITEMS; ++i) {
if (items[i] == data) { // now if it was found
items[i] = " "; // set it to your empty value
--totalItems; // prefix -- is faster then postfix one (no copy is created)
for (int j = i; j < MAX_ITEMS - 1; ++j) {
// stop at j < MAX_ITEMS - 1 because you wouldn't want
// to swap last element with the next because there
// is none behind it
if (items[j + 1] == " ")
// if the next item is already empty you don't need to shift any more
return true;
// swap the next item with much more
// efficient std::swap function
std::swap(items[j], items[j + 1]);
}
return true; // value is removed and items shifted so you can now return
}
}
// if function gets to this point that means the value wasn't found
return false;
}
If you would like to make your code more efficient, I can give you more suggestions on how to do it. This above should answer your question.
Also using an array for a struct like this isn't optimal at all. Using linked listed would mean no shifting would be required.
Edit: replaced long text with a code example
Edit2: added return statement if shifting is no longer necessary
FOR me it's unclear what you want to do as unavailability of full code to run.
But I think this should work as of what I think yo want to do
bool List::remove(const string& data){
for (int i = 0; i < totalItems; i++)
{
if (items[i] == data)
{
for (int j = i; j < totalItems-1; j++)
{
items[j] = items[j+1];
}
totalItems--;
return true;
}
}
return false;
if (inList(data) == true || data.empty() == true)
{
return false;
}
If the data parameter is in your list object, you return without removing anything? this should be !inList(data)
Additionally, when you make it into the loop below this code this loop:
for (int j = i; j < MAX_ITEMS; j++)
{
items[j] = items[j + 1];
items[MAX_ITEMS - 1] == " ";
break;
}
will only execute for j=i, the "break" statement will stop execution of this inner loop, and go back to the outer loop.
EDIT: this is how I personally would go about this problem.
bool List::remove(const string& data)
{
bool retVal;
if (!inList(data) || data.empty())
{
retVal = false;
}
else{
for (int i = 0; i < MAX_ITEMS; i++)
{
if (items[i] == data)
{
items[i] = " ";
for (int j = i; j < (MAX_ITEMS - 1); j++)
{
items[j] = items[j + 1];
}
items[MAX_ITEMS-1] = " ";
}
}
totalItems--;
retVal = true;
}
return retVal;
}

C++ adding extra, unwanted characters to a string

I am having a bug that I cannot find a fix for through google searching. I am attempting to make a text based version of the game Mastermind. I am using a string the is set from an array of chars as the criteria for a while loop. When the string is equal to "****" the game is supposed to tell the player that they won and exit, but for some reason a ^A is being added on to the end of the string that is being checked, even though it is not in the char array.
Here is the function that sets the char array and returns a string from that array:
string check(int guess[4], int num[4]) {
char hints[4];
cout << " ";
for (int i = 0; i < 4; i++) {
if (guess[i] == num[i]) {
hints[i] = '*';
cout << "*";
}
else {
for (int x = 0; x < 4; x++) {
if (guess[i] == num[x]) {
cout << "+";
}
}
}
if (guess[i] != num[i]) {
hints[i] = ' ';
}
}
string hint(hints);
cout << endl;
cout << hint << endl;
return hint;
}
And here is the function checking the value of the string:
while (hints.compare("****") != 0) {
if (guessCount == 5) {
break;
}
cout << "Guess?: ";
cin >> guess;
intToArray(guess, guessArr);
hints = check(guessArr, nums);
cout << hints << endl;
guessCount++;
}
if (hints.compare("****") == 0) {
cout << "You win! The number was: ";
for (int i = 0; i < 4; i++) {
cout << nums[i];
}
}
You haven't null-terminated the hints array, so you are getting extra garbage that is lying around on the stack in your string.
You could let the hint string know how long it is when you are constructing it.
string hint(hints, 4);
cout << endl;
cout << hint << endl;