Question

Write a main function that declares the names, marks, number of elements as well as the value to be searched for and the index of the returned function calls.

• Read and display the contents of names and marks.
• Ask the user for a name and using the linear search return the index to the user. If -1 is returned then the name is not in the file. Otherwise write out the name and mark for that student.
• Sort the arrays and write them out.
• Ask the user for a name to search for. This time use the binarySearch to return -1 or an index. Display the student’s name and mark if found.
• Test your program for found and not found for each type of search.

void getNames(string names[], int marks[], int& numElts);

int linearSearch(const string names[], int numElts,string who);

int binarySearch(const string names[], int numElts,string who);

void selectionSort(string names[], int marks[],int numElts);

void displayData(const string names[], const int marks[], int numElts);

const int NUM_Names = 20;

int main()

{

      string names[NUM_NAMES];

int marks[NUM_NAMES];

      int numElts;

int index;

      string searchWho;

// Function calls here

      return 0;

}

File for names and marks:

Collins,Bill 80

Smith,Bart 75

Allen,Jim 82

Griffin,Jim 55

Stamey,Marty 90

Rose,Geri 78

Taylor,Terri 56

Johnson,Jill 77

Allison,Jeff 45

Looney,Joe 89

Wolfe,Bill 63

James,Jean 72

Weaver,Jim 77

Pore,Bob 91

Rutherford,Greg 42

Javens,Renee 74

Harrison,Rose 58

Setzer,Cathy 93

Pike,Gordon 48

Holland,Beth 79

Answer 1

If you have any doubts, please give me comment...

#include <iostream>

#include <fstream>

#include <string>

using namespace std;

void getNames(string names[], int marks[], int &numElts);

int linearSearch(const string names[], int numElts, string who);

int binarySearch(const string names[], int numElts, string who);

void selectionSort(string names[], int marks[], int numElts);

void displayData(const string names[], const int marks[], int numElts);

const int NUM_NAMES = 20;

int main()

{

    string names[NUM_NAMES];

    int marks[NUM_NAMES];

    int numElts;

    int index;

    string searchWho;

    getNames(names, marks, numElts);

    cout<<"The names and marks in the file are: "<<endl;

    displayData(names, marks, numElts);

    cout<<"\n\nEnter search Name by using linear search: ";

    cin>>searchWho;

    index = linearSearch(names, numElts, searchWho);

    if(index!=-1)

        cout<<names[index]<<"\t"<<marks[index]<<endl;

    else

        cout<<"Name is not in the file"<<endl;

    

    cout<<"\nAfter sorted: "<<endl;

    selectionSort(names, marks, numElts);

    displayData(names, marks, numElts);

    cout<<"\nEnter search Name by using binary search: ";

    cin>>searchWho;

    index = binarySearch(names, numElts, searchWho);

    if(index!=-1)

        cout<<names[index]<<"\t"<<marks[index]<<endl;

    else

        cout<<"Name is not in the file"<<endl;

    return 0;

}

void getNames(string names[], int marks[], int &numElts){

    numElts = 0;

    ifstream inFile;

    inFile.open("input.txt");

    if(!inFile.fail()){

        while(!inFile.eof()){

            inFile>>names[numElts]>>marks[numElts];

            numElts++;

        }

    }

}

int linearSearch(const string names[], int numElts, string who){

    for(int i=0; i<numElts; i++){

        if(names[i]==who)

            return i;

    }

    return -1;

}

int binarySearch(const string names[], int numElts, string who){

    int l = 0, r = numElts-1;

    while (l <= r) {

        int m = l + (r - l) / 2;

        if (names[m] == who)

            return m;

        else if (names[m] < who)

            l = m + 1;

        else

            r = m - 1;

    }

    return -1;

}

void selectionSort(string names[], int marks[], int numElts){

    for(int i=0; i<numElts; i++){

        for(int j=i+1; j<numElts; j++){

            if(names[i]>names[j]){

                string temp = names[i];

                names[i] = names[j];

                names[j] = temp;

                int t = marks[i];

                marks[i] = marks[j];

                marks[j] = t;

            }

        }

    }

}

void displayData(const string names[], const int marks[], int numElts){

    for(int i=0; i<numElts; i++){

        cout<<names[i]<<"\t"<<marks[i]<<endl;

    }

}