let numberOfValues = Int(readLine()!)!
let values = readLine()!.characters.map { String($0) }
    
var currentElevation = 0
var valleyCount = 0
    
for i in (0...numberOfValues-1) {

    let currentStep = values[i]
        
    if (currentStep == "U") {
        currentElevation += 1
    } else {
        currentElevation -= 1
    }
        
    if (currentElevation == -1 && currentStep == "D") {
        valleyCount += 1
    }
        
}
    
print(valleyCount)