# First digit in factorial of a number in C++

C++Server Side ProgrammingProgramming

In this tutorial, we are going to write a program the finds the first digit of a factorial. Let's see an example.

Input − 7

Output − 5

Let's see the steps to solve the problem.

• Initialize the number

• Find the factorial of the number.

• Divide the number until it becomes a single digit.

## Example

Let's see the code.

Live Demo

#include <bits/stdc++.h>
using namespace std;
void findFirstDigitOfFactorial(int n) {
long long int fact = 1;
for (int i = 2; i <= n; i++) {
fact = fact * i;
}
while (fact >= 10) {
fact = fact / 10;
}
cout << fact << endl;
}
int main() {
int n = 7;
findFirstDigitOfFactorial(n);
return 0;
}

## Output

If you execute the above program, then you will get the following result.

5

## Conclusion

If you have any queries in the tutorial, mention them in the comment section.

Published on 29-Dec-2020 11:03:47