Description
Get a number as input from user and then check whether that number is a strong number or not.
A number is said to be strong number if the sum of the factorial of each digit in the number is same as that of the number.
E.g. let the number be 145
Here 1! + 4! + 5! is 1 + 24 + 120 which is equal to 145 itself.
Input
121
Output
Not a strong number
Input
2
Output
Strong number
C Program
Method 1
#include <stdio.h>
int main()
{
int num,rem,fact=1,sum=0;
printf("Enter a number: ");
scanf("%d",&num);
int copy=num;
if(num==0)
sum=sum+fact;
else
{
while(copy!=0)
{
rem=copy%10;
fact=1;
for(int i=1;i<=rem;i++)
{
fact=fact*i;
}
sum=sum+fact;
copy=copy/10;
}}
if(sum==num)
printf("Strong number");
else
printf("Not a strong number");
return 0;
}
Method 2
#include <stdio.h>
int factorial(int n)
{
if(n!=0)
return n * factorial(n-1);
else
return 1;
}
int main()
{
int num,rem,fact=1,sum=0;
printf("Enter a number: ");
scanf("%d",&num);
int copy=num;
if(num==0)
sum=sum+fact;
else
{
while(copy!=0)
{
rem=copy%10;
fact=factorial(rem);
sum=sum+fact;
copy=copy/10;
}}
if(sum==num)
printf("Strong number");
else
printf("Not a strong number");
return 0;
}
C++ Program
Method 1
#include <iostream>
using namespace std;
int main()
{
int num,rem,fact,sum=0;
cout<<"Enter a number: ";
cin>>num;
int copy=num;
if(num==0)
sum=sum+fact;
else
{
while(copy!=0)
{
rem=copy%10;
fact=factorial(rem);
sum=sum+fact;
copy=copy/10;
}}
if(sum==num)
cout<<"Strong number";
else
cout<<"Not a strong number";
return 0;
}
Method 2
#include <iostream>
using namespace std;
int factorial(int n)
{
if(n!=0)
return n * factorial(n-1);
else
return 1;
}
int main()
{
int num,rem,fact=1,sum=0;
cout<<"Enter a number: ";
cin>>num;
int copy=num;
if(num==0)
sum=sum+fact;
else
{
while(copy!=0)
{
rem=copy%10;
fact=factorial(rem);
sum=sum+fact;
copy=copy/10;
}}
if(sum==num)
cout<<"Strong number";
else
cout<<"Not a strong number";
return 0;
}
Java
import java.util.Scanner;
public class Main
{
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.print("Enter a number: ");
int num=sc.nextInt();
int fact=1,sum=0;
int copy=num;
if(num==0)
sum=sum+fact;
else{
while(copy!=0)
{
fact=1;
int rem=copy%10;
for(int i=1;i<=rem;i++)
fact=fact*i;
sum=sum+fact;
copy=copy/10;
}}
if(sum==num)
System.out.println("Strong Number");
else
System.out.println("Not a Strong Number");
}
}
Python
Method 1
num=int(input("Enter a number: "))
fact=1
Sum=0
copy=num
if(num==0):
Sum=Sum+fact
else:
while(copy!=0):
fact=1
rem=copy%10
for i in range(1,rem+1):
fact=fact*i
Sum=Sum+fact
copy=copy//10
if(Sum==num):
print("Strong number")
else:
print("Not a strong number")
Method 2
import math
num=int(input("Enter a number: "))
Sum=0
fact=1
copy=num
if(num==0):
Sum=Sum+fact
else:
while(copy!=0):
rem=copy%10
fact=math.factorial(rem)
Sum=Sum+fact
copy=copy//10
if(Sum==num):
print("Strong number")
else:
print("Not a strong number")
