Counting Valleys

import java.io.*;
import java.math.*;
import java.security.*;
import java.text.*;
import java.util.*;
import java.util.concurrent.*;
import java.util.regex.*;

public class Solution {

    // Complete the countingValleys function below.
    static int countingValleys(int n, String s) {

    	char[] steps=s.toCharArray();
    	int alt=0,valley=0;
    	for (int i = 0; i < steps.length; i++) {
			if(steps[i]=='U')
			{
				alt++;
				if (alt==0) {
					valley++;	
					}
			}
			else if(steps[i]=='D')
			{
				alt--;
				
			}
			else
			{
				//Invalid Input
			}
		}
return valley;
    }

    private static final Scanner scanner = new Scanner(System.in);

    public static void main(String[] args) throws IOException {

        int n = scanner.nextInt();
        scanner.skip("(\r\n|[\n\r\u2028\u2029\u0085])?");

        String s = scanner.nextLine();

        int result = countingValleys(n, s);
System.out.println(result);


        scanner.close();
    }
}