Question

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


/* Write a function checkPrime such that
input: an int
output: boolean
function: Return true if the number is a prime number and return false otherwise
*/
//TO DO **************************************






/* Write a function checkPrime such that
input: an array of int and size of array
output: nothing
function: Display the prime numbers of the array
*/
//TO DO **************************************









/* Write a function SumofPrimes such that
input: an int
output: nothing
function: Check whethe a given number can be expressed as a sum of two prime number, then display (cout) two prime numbers if it is possible
If there are multiple prime numbers that can be sum up, you should display all of them. (check the main below)
*/
//TO DO **************************************











/* Write a function printArray such that
input: pointer to the last element of array, and int which is length of array
output: nothing
function: Display (cout) the element of array in order
Hint: array is the consequencial in the memory
*/
//To DO *****************************************











/* Write a function checkPalindrome_String such that
input: String
output: boolean
function: Check whethe a given string is palindrome. It means if I reverse it, it would be the same. like Hannah , Bob
Hint: string is like an array of character ; s.size() returns the size of string s
*/
//TO DO **************************************












/* Bonus Point: Write a function checkPalindrome_Integer such that
input: int
output: boolean
function: Display (cout) the reverse of the integer, and return true if the number and its reverse are equal
Hint: you can use % to get the digit of numbers
*/
//TO DO **************************************










int main()
{
        /* The output of this section should be
        This prime numbers are : 2, 7, 11
        */
        int A[5] = { 2,55, 7, 44, 11 };
        cout<< "The output should be 2,7,11, your output is "<<findPrime(A, 5);


        /* The output of this section should be 
        34 = 3 + 31 
        34 = 5 + 29
        34 = 11 + 23
        34 = 17 + 17
        */
        SumofPrimes(34);
        
        
        
        /* This should print the A in order from the beginning  2 55 7 44 11*/
        print_array(&A[4], 5);
        
        
        
        //This should return true
        cout << checkPalindrom_String("HANNAH");
        

        //This should return 654321
        cout << checkPalindrom_Integer(123456) << endl;

        return 0;
}

Answer 1

/******************* Your code is as follow **************************************************************************************/

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

/* Write a function checkPrime such that
input: an int
output: boolean
function: Return true if the number is a prime number and return false otherwise
*/
bool checkPrime(int n){
bool check=true;
for(int i = 2; i <= n / 2; i++)
{
if(n % i == 0)
{
check = false;
break;
}
}
if (check)
return true;
else
return false;
}

/* Write a function checkPrime such that
input: an array of int and size of array
output: nothing
function: Display the prime numbers of the array
*/
void findPrime(int a[],int len){
for(int i = 0; i < len; i++){
bool check = checkPrime(a[i]);
if(check == true)
cout << a[i] << " ";
  
}
cout << endl;
  
}

/* Write a function SumofPrimes such that
input: an int
output: nothing
function: Check whethe a given number can be expressed as a sum of two prime number, then display (cout) two prime numbers if it is possible
If there are multiple prime numbers that can be sum up, you should display all of them. (check the main below)
*/
void SumofPrimes(int num){
int i;
for(i = 2; i <= num/2; i++)
{
if (checkPrime(i)) //check the 1st component of number
{
if (checkPrime(num - i)) //check the another part of number
{
cout << num << " = " << i << " + " << num-i << endl;
}
}
}

}

/* Write a function printArray such that
input: pointer to the last element of array, and int which is length of array
output: nothing
function: Display (cout) the element of array in order
Hint: array is the consequencial in the memory
*/
void print_array(int *num, int len){
int cnt = 0;
int *intPtr = num-(len-1);
while( *intPtr != NULL && cnt < len )
{
cout<<*intPtr<<" ";
intPtr++;
cnt++;
}
}

/* Write a function checkPalindrome_String such that
input: String
output: boolean
function: Check whethe a given string is palindrome. It means if I reverse it, it would be the same. like Hannah , Bob
Hint: string is like an array of character ; s.size() returns the size of string s
*/
bool checkPalindrom_String(string str){
int len = str.length();
int i;
bool check=true;
for(i=0; i < len; i++){
if(str[i] != str[len-i-1]){
check = false;
break;
}
}
return check;
}

/* Bonus Point: Write a function checkPalindrome_Integer such that
input: int
output: boolean
function: Display (cout) the reverse of the integer, and return true if the number and its reverse are equal
Hint: you can use % to get the digit of numbers
*/

bool checkPalindrom_Integer(int num){
int rem;
int revNum = 0;
while(num != 0)
{
rem = num%10;
revNum = revNum*10 + rem;
num = num/10;
}
  
cout << "Reverse of given integer:" << revNum << endl;
if(num == revNum)
return true;
else
return false;
}

int main()
{
/* The output of this section should be
This prime numbers are : 2, 7, 11
*/
int A[5] = { 2,55, 7, 44, 11 };
cout << "The output should be 2,7,11, your output is ";
findPrime(A, 5);

/* The output of this section should be
34 = 3 + 31
34 = 5 + 29
34 = 11 + 23
34 = 17 + 17
*/
SumofPrimes(34);
  
  
  
/* This should print the A in order from the beginning 2 55 7 44 11*/
print_array(&A[4], 5);
  
  
  
//This should return true
cout << endl;
cout << checkPalindrom_String("HANNAH");
  
cout << endl;
//This should return 654321
cout << checkPalindrom_Integer(123456) << endl;

return 0;
}

/*************************************************** Screen shot of output ******************************************************/