function processData(input) {
    input = input.split('\n');
    var walk = input[1].split('');
    
    var count = 0;
    var sea = true;
    var valleys = 0;
    
    walk.forEach((step)=>{
        if(step==='U'){
            count++;
        } else {
            count--;
        }
        
        if(count === 0){
            sea = true;
        } else if (count!== 0 && sea === true){
            sea = false;
            if(count<0){
                valleys++;
            }
        }
    });
    console.log(valleys);
} 

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

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