Recursive Function help/ Vector

[lew13]

I am trying to write a small program that takes a string of positive integers and counts the to the end of the string using the most cost efficient route. It can only move 1 or 2 positions, so it can't jump from the first integer to the last. So 1 23 3 5 4. Anyhow, right now I am trying to figure out how to push the input string into a vector and I am running into trouble on lines 37-42 in my while loop.

#include <iostream>
#include <vector>
#include<string>
#include<sstream>

using namespace std;


/*void cost (int index)
        {
            if (index == gameBoard.back())
                return gameBoard.back();

            else
        {
           int costOne = cost (index + 1);
           int costTwo = cost (index + 2);

		   return min(costOne,costTwo) + gameBoard[index];

        }*/

int main()
{
    char goAgain;

	do{

    cout << "Please enter the numbers of a game board on one line, separating numbers by spaces,then press the Enter key." << endl ;
    string input;
    getline (cin, input);
    int i;
    vector<string> gameBoard;

    stringstream inputStringStream(input);

    while (inputStringStream >> i)
    {
        gameBoard.push_back(inputStringStream);
        for (int i = 0; i < gameBoard.size(); i++)
        cout << gameBoard[i] << endl;
    }


	cout << "Would you like to enter a new Game Board (Y/N)?" << endl;
	cin >> goAgain;

    cin.ignore(9999, '\n');

	}while(goAgain == 'Y'|| goAgain == 'y');





 return 0;
}

[fg109]

Your problem is on line 39. What do you think you're trying to push?

[lew13]

The input string into the vector is what I am trying to have it push.

[lew13]

Ah I didn't have input. I had inputStringStream.

[fg109]

Don't you think that you should be trying to push i? You know, the variable that you just stored the number you got from inputStringStream, instead of the stream itself?

EDIT: Actually, that doesn't make sense either, since gameBoard is a vector of strings, not int... Show an example of your input and what you want as output.

[lew13]

I tried, but it wouldn't work either.

[lew13]

It gives more errors

stringstream inputStringStream(input);

    while (inputStringStream >> i)
    {
        gameBoard.push_back(input);
        for (int i = 0; i < gameBoard.size(); i++)
        cout << gameBoard[i] << endl;

I have this now and it works, but it prints way more copies than I anticipate I assume it's because I have i < gameBoard.size(), but I don't know a different way to put the statement, and I tried just printing the vector, but that crashes.

[fg109]

fg109 wrote:

Show an example of your input and what you want as output.

[lew13]

Please enter the number of a Gameboard on one line, separate the numbers by spaces, when finished press the Enter key.

1 2 3 4 5

1 2 3 4 5
1 2 3 4 5
1 2 3 4 5
1 2 3 4 5
1 2 3 4 5
1 2 3 4 5
1 2 3 4 5
...it prints 15 lines of the same thing.

[fg109]

I'm asking what you want it to print out, not what it is printing out.

[lew13]

Oh sorry.

Input: 1 2 3 4 5

Output: A single line 1 2 3 4 5.

I am just trying to get everything correct before I start on the recursion function.

[fg109]

OK... I'm not sure why you want to use loops and vectors and stringstreams and stuff to do that.

getline(cin, input);
cout << input;

^Wouldn't that be enough? If you insist on using loops and vectors and stringstreams, this is how you do it:

getline (cin, input);
int i; //you really should rename this variable so you don't
       //confuse it with the one that you use for the for loop
vector<int> gameBoard;

stringstream inputStringStream(input);

while (inputStringStream >> i)
	gameBoard.push_back(i);

for (int i = 0; i < gameBoard.size(); i++)
	cout << gameBoard[i] << ' ';

^Changed the relevant parts of your code.

[lew13]

Well I have to put it into a vector, because it is a virtual "gameboard" and once I have the numbers stored in the vector I have to use my recursive function to count the most cost efficient route to the end of the gameboard. Right now I am just trying to have a program that runs properly and once I have that I will use the vector in my recursive function. Thanks for the help, do you know much about recursion?

[lew13]

I have most of it down now I am having trouble with lines 13-14, my recursion call. This is what I have and I am trying to make it so the function will return the lowest value each time it moves up the index, but it is limited to moving only 1 or 2 spaces forward at a time. Once it has figured this out it will return the lesser of the two values.

int cost (vector<int> gameBoard, int index)
        {
            if (index > 1)
            {
                int costOne = cost(index + 1);
                int costTwo = cost(index + 2);

                return min(costOne,costTwo) + gameBoard[index];
            }

            else if (index == 0 || index == 1)
                return index;
        }

[fg109]

I don't understand how your function is supposed to do what you want it to do, even if it compiles. But as for why it's not compiling, lines 5 and 6 of the code you posted are wrong. Your function cost is supposed to take 2 parameters; you are only providing 1. Another thing is, how does your function know to stop when it hits the end of the vector?

[lew13]

So would I want something more like this?

 int costOne = cost(gameBoard, (index-1));
 int costTwo = cost(gameBoard, (index-2));

This compiles, but every time it's run it just prints 1, no matter the input.

I was assuming that once it was running that when it got to the index being equal to 1 or 0 it would end the recursion, but now that I type it, it sounds like it won't work.

[fg109]

No, it'll work. It didn't make sense before because you had index + 1 instead of index - 1 which meant it would have kept increasing without limits.

[lew13]

int costOne = cost(gameBoard.at(index-1));

So would I want it this way? Because when I try it this way it doesn't compile and when I have it as I do in my last post it compiles, but only ever returns 1.

[lew13]

To print what the function is returning I would just have

cout<<cost;

right?

[TarikNeaj]

If your function has parameters, then you need that too.

cout << cost(something);