## Introduction

I have used Code::blocks 12 compiler for debugging purpose. But you can use any C programming language compiler as per your availability.

#include <stdio.h> // Function declarations long long fact(int num); void printStrongNumbers(int start, int end); int main() { int start, end; /* Input start and end range */ printf("Enter the lower limit: "); scanf("%d", &start); printf("Enter the upper limit: "); scanf("%d", &end); printf("List of strong numbers between %d to %d are: \n", start, end); printStrongNumbers(start, end); return 0; } //Printing all strong numbers in a given range void printStrongNumbers(int start, int end) { long long sum; int num; // Iterates from start to end while(start != end) { sum = 0; num = start; // Calculating sum of factorial of digits while(num != 0) { sum += fact(num % 10); num /= 10; } // If sum of factorial of digits equal to current number if(start == sum) { printf("%d ", start); } start++; } } //Recursively find factorial of any number long long fact(int num) { if(num == 0) return 1; else return (num * fact(num-1)); }