Question

This lab will combine reading data from a file and searching the array to find a specific value.

Assignment

Write a program that reads in a file full of strings into an array, and prompts the user for a string to find in the array. The program should loop until a sentinel value (such as -1) is entered.

After looping in main() for the input, write a search function, with the following prototype:

int findWord(string [], int, string);

with arguments as follows:

1) The first argument, a string[] (array), is list of words read from the file.

2) The second argument, an 'int', is the maximum size of the file (define a constant such as MAX_SIZE in main(), not as a global variable, and pass it into this function here).

3) The third argument, a 'string', is requested word to be found.

The return 'int' should be the position in the array where the word appears (starting with 0 for the first word) or the value -1 if the word is not present in the array.

The input file is a list of dictionary words -- dictionary.txt -- which you can find in this week's module.

How to Search

In your findWord function, use the linear search algorithm, which starts at the beginning of the array and then steps through the elements sequentially until either the desired value is found or the end of the array is reached.

For example, if the array is:

{ "hello", "goodbye", "sometimes", "never" }

and we want to find the word "sometimes", the algorithm would check each element, starting with "hello", to see if it is equal to the search key. When the search reaches either the found word or the end of the array, the algorithm stops.

Example Output

Enter the word to find (-1 to exit): abacus
The word "abacus" is in the file at position 8884.
Enter the word to find (-1 to exit): life
The word "life" is in the file at position 1.
Enter the word to find (-1 to exit): -1

What to Submit

Upload your main.cpp file (source code for your solution) and a screenshot of a single run with at least two lookups and an exit (i.e. entering '-1) to stop the program.

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Answer 1

#include<iostream>
#include<fstream>
#include <bits/stdc++.h>
using namespace std;

int findWord(string arr[], int MAX_SIZE, string word)
{
// Iterate over array
// if current word is equal to target
// return index
for(int i =0; i<MAX_SIZE; i++)
{
if(arr[i]==word)
{
return i;
}
}
// return -1 means word was not found
return -1;
}

int main()
{
// I have defined this 2, you can change it later
int const MAX_SIZE = 20;
fstream fileIn;
string filename = "dictionary.txt";
// Open file to read
fileIn.open(filename.c_str());

// Check if file exists
if(!fileIn)
{
cout<<"File cannot be opened!"<<endl;
return 0;
}

// Create an array of size MAX_SIZE
string arr[MAX_SIZE];
// index variable for array indexing
int index = 0;
string word = "";
// Iterate loop till the last word
while(fileIn>>word)
{
// add word to array
// increment index by 1
arr[index] = word;
index++;

}

string w;
// Ask user to enter a word to search
cout<<"Enter the word to find (-1 to exit): ";
cin>>w;
// Iterate a loop till user doesn't enter -1
while(w!="-1")
{
// call function to find word
// if position is -1, means word does not exists
// else print the location of word
int position = findWord(arr,MAX_SIZE,w);
if(position==-1)
{
cout<<"The word "<<w<<" doesn't exist in file"<<endl;
}
else
{
cout<<"The word "<<w<<" is in the file at position "<<(position+1)<<endl;
}
cout<<"Enter the word to find (-1 to exit): ";
cin>>w;
}
return 0;
}

INPUT FILE I USED

amateur
life
soul
sole
math
science
therapy
abacus
mine
toll
love
hate
abuse
marry
lenses
pair
fair
fare
mature
mint

OUTPUT-

E:Practice\Chegglbin\Release\ Chegg.exe Enter the word to find (-1 to exit): abacus e word abacus is in the file at position 8 Enter the word to find (-1 to exit): life The word life is in the file at position 2 Enter the word to find (-1 to exit): most The word most doesn't exist in file Enter the word to find (-1 to exit): -1 execution time: 8.685 s Process returned e (exe) Press any key to continue.