Question

2 Happy Numbers 2.1 Definition The definition of a happy number, from wikipedia Given a number n = no, define a sequence n1, n2, … where ni+1 1S the sum of the squares of the digits of n,. Then n is happy if and only if there exists i such that ni 1 It can be shown (see wikipedia) that n is unhappy if the number 4 appears in the sequence. 2.2 The program Write a C++ program happy.cpp which reads numbers, one at a time, from the terminal input, and outputs x is happy or x is not happy For example: > happy 4 is not happy 1 is happy 1000 1000 is happy Your program should handle the calculation of happiness for all numbers betweern 1 and 2147483647 Your program should continue answering about the happiness of numbers until 0 is entered, at which time the program should exit silently

Answer 1

#include <iostream>

using namespace std;

int happySum(int n){

int sum = 0;

while(n > 9){

sum = 0;

while(n!=0){

int r = n % 10;

sum = sum + r * r;

n = n/10;

}

n=sum;

}

return n;

}

int isHappy(int n){

n = happySum(n);

if( n == 1 || n == 4){

return 1;

}

return 0;

}

int main()

{

int i;

while(1) {

cout<<"Enter a number: ";

cin>>i;

if(i==0)

break;

if(isHappy(i)){

cout<<i<<" is Happy"<<endl;

}else{

cout<<i<<" is not Happy"<<endl;

}

}

return 0;

}


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See Output


null

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