C++ Exercises: Find the Lychrel numbers and the number of Lychrel number within the range 1 to 1000

C++ Numbers: Exercise-12 with Solution

Write a program in C++ to find the Lychrel numbers and the number of Lychrel number within the range 1 to 1000 (after 500 iteration).

Pictorial Presentation:

Sample Solution:

C++ Code :

#include <iostream>
using namespace std;


long long int numReverse(long long int number)
{
    long long int rem = 0;
    while (number > 0)
    {
    rem = (rem * 10) + (number % 10);
        number = number / 10;
    }
    return rem;
}
bool is_Palindrome(long long int num)
{
    return (num == numReverse(num));
}
bool isLychrel(int num, const int iterCount = 500)
{
    long long int temp = num;
    long long int rev;
    for (int i = 0; i < iterCount; i++)
    {
        rev = numReverse(temp);
        if (is_Palindrome(rev + temp))
            return false;
        temp = temp + rev;
    }
    return true;
}
int main()
{
int lyno,ctr=0,i;
bool l;
 cout << "\n\n Find the Lychrel numbers between 1 to 1000(after 500 iteration): \n";
 cout << " ----------------------------------------------------------------------\n";
 cout << " The Lychrel numbers are : ";
for (i=1;i<=1000;i++)
{
lyno=i;
    l = isLychrel(lyno);
    if(l==1)
    {
	ctr++;
        cout<<lyno<<" ";
    }}
    cout<<endl;
    cout <<" The number of Lychrel numbers are: "<<ctr<<endl;
    return 0;

}

Sample Output:

Find the Lychrel numbers between 1 to 1000(after 500 iteration):                                    
 ----------------------------------------------------------------------                              
 The Lychrel numbers are : 196 295 394 493 592 689 691 788 790 879 887 978 986                       
 The number of Lychrel numbers are: 13 

Flowchart:

C++ Code Editor:

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