An avid hiker keeps meticulous records of their hikes. During the last hike that took exactly steps, for every step it was noted if it was an uphill, , or a downhill, step. Hikes always start and end at sea level, and each step up or down represents a unit change in altitude. We define the following terms:
- A mountain is a sequence of consecutive steps above sea level, starting with a step up from sea level and ending with a step down to sea level.
- A valley is a sequence of consecutive steps below sea level, starting with a step down from sea level and ending with a step up to sea level.
Given the sequence of up and down steps during a hike, find and print the number of valleys walked through.
Example
The hiker first enters a valley units deep. Then they climb out and up onto a mountain units high. Finally, the hiker returns to sea level and ends the hike.
Function Description
Complete the countingValleys function in the editor below.
countingValleys has the following parameter(s):
- int steps: the number of steps on the hike
- string path: a string describing the path
Returns
- int: the number of valleys traversed
Input Format
The first line contains an integer , the number of steps in the hike.
The second line contains a single string , of characters that describe the path.
Constraints
Sample Input
8
UDDDUDUU
Sample Output
1
Explanation
If we represent _ as sea level, a step up as /, and a step down as \, the hike can be drawn as:
_/\ _
\ /
\/\/
The hiker enters and leaves one valley.