lab8.cpp

#include <iostream>
#include <cstdlib>
#include <cctype>
#include <ctime>
#include <string>


//function prototypes for the recursive functions
int sumOfNumbers(int);
bool isMember(int*, int, int);
std::string stringReverser(std::string, int);
bool isPalindrome(std::string);
int multiply(int, int);
int recursiveMultiplication(int,int);

const int ARRAY_SIZE = 10;

int main()
{
    int choice, num, num1, num2;
    int myArray[ARRAY_SIZE];
    srand(time(NULL));
    std::string userString, userStrWithoutSpaces;

    do{

        std::cout << "\n\nWhat do you want to do?\n";
        std::cout << "\t1.  Sum of Numbers\n";
        std::cout << "\t2.  IsMember Array Function\n";
        std::cout << "\t3.  String Reverser\n";
        std::cout << "\t4.  Palindrome Detector\n";
        std::cout << "\t5.  Recursive Multiplication\n";
        std::cout << "\t6.  End the Program\n";
        std::cout << "CHOOSE 1-6:  ";
        std::cin >> choice;
        while(choice < 1 || choice > 6)
        {
            std::cout << "\nInvalid input!  CHOOSE 1-6:  ";
            std::cin >> choice;
        }
        switch(choice)
        {
            case 1:
                std::cout << "\n\nSUM OF NUMBERS\n";
                std::cout << "Enter an integer:  ";
                std::cin >> num;
                std::cout << "\nThe result is: " << sumOfNumbers(num) << std::endl; //print out the result of the sumOfNumbers function here

                break;


            case 2:
                for(int x=0; x<ARRAY_SIZE; x++)
                {
                    myArray[x] = (rand()%100)+1;
                }
                std::cout << "\n\nISMEMBER ARRAY FUNCTION\n";
                std::cout << "Enter an integer:  ";
                std::cin >> num;
                std::cout << "\nHere are the array values:  ";
                for(int x=0; x<ARRAY_SIZE; x++)
                {
                    std::cout << myArray[x] << " ";
                }
                //print if the value that the user entered is in the array or not here
                if(isMember(myArray, num, ARRAY_SIZE))
                    std::cout << "\nYour integer " << num << " is in the array." << std::endl;
                else
                    std::cout << "\nYour integer " << num << " is not in the array." << std::endl;

                break;


            case 3:
                std::cout << "\n\nSTRING REVERSER\n";
                std::cout << "Enter a string and I will reverse it:  ";
                std::cin.ignore();
                getline(std::cin, userString);
                //call string reverser function here
                std::cout << stringReverser(userString, ARRAY_SIZE) << std::endl; //prints with a question mark before

                break;


            case 4:
                std::cout << "\n\nPALINDROME DETECTOR\n";
                std::cout << "Enter a string and I will tell you if it is a palindrome:  ";
                std::cin.ignore();
                getline(std::cin, userString);

                //change string to be all uppercase
                for(int x=0; x<userString.length(); x++)
                {
                    userString[x] = toupper(userString[x]);
                }

                //remove spaces from string
                userStrWithoutSpaces = userString;
                for(int x=0; x<userStrWithoutSpaces.size(); x++)
                {
                    if(userStrWithoutSpaces[x] == ' ')
                        userStrWithoutSpaces.erase(x, 1);
                }
                //print out whether the user's string is a palindrome or not here.
                //when you print out the user's string, print out the uppercase version that doesn't have the spaces removed.
                if (!isPalindrome(userString))
                {
                    std::cout << "Your string " << userString <<" is a palindrome." << std::endl;
                    std::cout << "Reversed: " << stringReverser(userString,userString.length()) << std::endl;
                }
                else
                    std::cout << "Your string is not a palindrome." << std::endl;
                break;


            case 5:
                std::cout << "\n\nRECURSIVE MULTIPLICATION\n";
                std::cout << "Enter in the first integer:  ";
                std::cin >> num1;
                std::cout << "\nEnter in the second integer:  ";
                std::cin >> num2;
                //print out the value returned from the multiply function here
                std::cout << "\nThe result is: " << recursiveMultiplication(num1, num2) << std::endl;

                break;

        }
    }while(choice != 6);

    std::cout << "\n\nGOODBYE!\n\n";
    return 0;
}


//implement the five recursive functions below!!!!
//done

int sumOfNumbers(int n)
{
    if(n!=0)
    {
    return n+sumOfNumbers(n-1);
    }
    return 0;
}

bool isMember(int a[],int val,int size)
{
    if(size<1)
    return false;
    else if(a[size]==val)
    return true;
    else
    return isMember(a,val,size-1);
}

std::string stringReverser(std::string s,int n)
{
    if(n==0)
    return "";
    std::string last(1,s[n-1]);
    std::string reversed=stringReverser(s,n-1);
    return last+reversed;
}

bool isPalindrome(std::string str)
{
    if(str.length() <= 1)
    return true;
    if(str[0] == str[(str.length()-1)])
    {
    return isPalindrome(str.substr(1,str.length()-1));
    }
    else
    return false;
}

int recursiveMultiplication(int x,int y)
{
    static int product=0,i=0;
    if(i<x)
    {
    product=product+y;
    i++;
    recursiveMultiplication(x,y);
    }
    return product;
}