function processData(input) {
    let s = input.split("\n");
    let length = s[0];
    let data = s[1];let seaLevel=0;
	let aboweSeaLevel=true;
	let valley=0;
	for(let i=0;i<length;i++){
		seaLevel+=data[i]=="U"?1:-1;
		if(seaLevel<0){
			if(aboweSeaLevel)
				valley++;
			aboweSeaLevel = false;
		}
		if(seaLevel>=0 && !aboweSeaLevel)
			aboweSeaLevel=true;
	}
	console.log(valley);
} 

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

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