﻿ Java - Compute the number of trailing zeros in a factorial

# Java: Compute the number of trailing zeros in a factorial

## Java Basic: Exercise-112 with Solution

Write a Java program to compute the number of trailing zeros in a factorial.

Example
7! = 5040, therefore the output should be 1.

Pictorial Presentation:

Sample Solution:

Java Code:

``````import java.util.Scanner;

public class Example112 {
public static void main(String[] arg) {
Scanner in = new Scanner(System.in); // Create a Scanner object for user input
System.out.print("Input a number: "); // Prompt the user to input a number
int n = in.nextInt(); // Read and store the user's input as 'n'
int n1 = n; // Create a copy of 'n' to preserve the original value
long ctr = 0; // Initialize a variable 'ctr' to count trailing zeros

while (n != 0) {
ctr += n / 5; // Count the number of trailing zeros by dividing 'n' by 5 and accumulating the result
n /= 5; // Reduce 'n' by dividing it by 5 for the next iteration
}
System.out.printf("Number of trailing zeros of the factorial %d is %d ", n1, ctr); // Print the result
System.out.printf("\n"); // Print a new line
}
}
```
```

Sample Output:

```Input a number : 5040
Number of trailing zeros of the factorial 5040 is 1258
```

Flowchart:

Java Code Editor:

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