Study Resource 10 – NYU Bridge to Tandon Program

/*

Implement the function:
string* createWordsArray(string sentence, int& outWordsArrSize)

This function gets a string sentence containing a sentence.
When called, it should create and return a new array (of strings), that contains all the
words in sentence. The function should also update the output parameter,
outWordsArrSize, with the logical size of the new array that was created.

Note: Assume that the words in the sentence are separated by a single space.
For example, if sentence=”You can do it”, after calling
createWordsArray(sentence, outWordsArrSize), the function should create
and return an array that contains [”You” , ”can” , ”do” , ”it”], and update the
value in outWordsArrSize to be 4.

Implementation requirements:
1. You may want to use some of the string methods, such as find, substr, etc.
2. Your function should run in linear time. That is, if sentence contains n characters,
your function should run in O(n).
3. Write a main() program that tests this function..

*/

#include <iostream>
#include <string>
using namespace std;

string* createWordsArray(string sentence, int& outWordsArrSize);
void printArrElem(string* arr, int arrSize);


int main() {

    string sentenceEntered;
    int outWordsArrSize;
    string* stringArr;

    cout << "Enter a sentence: ";
    getline(cin, sentenceEntered);

    stringArr = createWordsArray(sentenceEntered, outWordsArrSize);

    printArrElem(stringArr, outWordsArrSize);

    delete [] stringArr;
}

string* createWordsArray(string sentence, int& outWordsArrSize){

    string* wordsArray = new string [1];

    int arrPhysicalSize = 1;
    int i = 0;
    string word;

    int wordCounter = 0;
    int sentenceLength = sentence.length();

    while(sentenceLength >= 0){


        if(sentence[i] == ' ' || sentence[i] == '\0'){

            if(wordCounter > 0){
                string* newLinesArr;
                newLinesArr = new string[arrPhysicalSize*2];
                for(int i = 0; i < wordCounter; i++)
                    newLinesArr[i] = wordsArray[i];
                delete []wordsArray;
                wordsArray = newLinesArr;
                arrPhysicalSize *= 2;
            }

            wordsArray[wordCounter] = word;
            wordCounter++;

            word = "";

        }else{
            word += sentence[i];
        }


        i++;
        sentenceLength--;

    }

    outWordsArrSize = wordCounter;
    return wordsArray;

}

void printArrElem(string* arr, int arrSize){
    cout << "New Size: " << arrSize << endl;
    cout << "[";
    for(int i=0; i < arrSize; i++){
        cout << "'" << arr[i] << "'";
        if(i != arrSize - 1){
            cout << ",";
        }
    }
    cout << "]";
}