function processData(input) {
    //Enter your code here
    input = input.split('\n')[1];
    var valleyCount = 0;
    var currentPosition = 0, valleyFlag = false;
    for(var i=0;i<input.length;i++){
        if(input[i]=='U'){
            currentPosition++;
        }else{
            currentPosition--;
        }
        
        if(currentPosition < 0){
            valleyFlag = true;
        }
                
        if(valleyFlag == true && currentPosition == 0){
            valleyFlag = false;
            valleyCount++;
        }
    }
    console.log(valleyCount);
} 

process.stdin.resume();
process.stdin.setEncoding("ascii");
_input = "";
process.stdin.on("data", function (input) {
    _input += input;
});

process.stdin.on("end", function () {
   processData(_input);
});