//Program to demonstrate some for loops
import java.util.Scanner;
class SpaceCount
{
	public static void main(String [] args)
	{
		Scanner input = new Scanner(System.in);
		
		//We calculate the factorial of a number.
		/* The factorial of a number is defined as the product of all the numbers from 1 to the number itself.
		 * For example, the factorial of 5, denoted as 5! = 1*2*3*4*5 = 120
		 * This loop starts at 1, and keeps a running product. At each iteration, multiply the current product with the current number.
		 */
		System.out.println("Enter a number: ");
		int num = input.nextInt();
		int product = 1;
		for(int i =1;i<=num;i++) //we count up from 1 till the number
		{
			product = product * i;
		}
		System.out.println("The factorial is "+product);

		/* This part counts the number of spaces in a piece of text.
		 * We move through the string, reading one character at a time.
		 * If the character we just read in happens to be a space, we increment a counter.
		 * The method getChar(index), of the String class returns the character at the given index.
		 * The method length(), of the String class, returns the length of the String. 
		 * If the length of a string is 'k', then the string has characters from index 0 to k-1
	 	 */
		System.out.println("Enter your text: ");
		String junk=input.nextLine();//consume the preceding newline
		String text = input.nextLine();
		int count=0; //counter.
		int length= text.length();// This Java method gets the length of the string
		/*strings are 0 indexed*/
		for(int pos=0;pos<length;pos++)
		{
			//grab each letter and check if it is a space
			char letter = text.charAt(pos);
 			if(letter == ' ')
				count++;
		}
		System.out.println("The space count is "+count);
		
		//Hey, we're printing a centered triangle
		/* This is an example of nested for loops.
		 * We assume a triangle is built with the * character and spaces.
		 * The logic for centering: each line l requires numLines - l number of spaces before the first star.
		 * Putting a space after each star will then automatically take care of the centering.
		 */
		System.out.print("Enter the number of lines: ");
		int numLines = input.nextInt();
		//This for loops prints one line for each iteration.
		for(int i=0;i<numLines;i++)
		{
			//This for loop takes care of the preceding spaces in each line.
			for(int j=0;j<numLines-i-1;j++)
				System.out.print(" ");
			//This for loop prints the required number of characters in each line.
			for(int k=0;k<=i;k++)
				System.out.print("* ");
			//We are done with a line. Moving on to the next one.
			System.out.println();
		}
		
	}
}