#include<bits/stdc++.h> using namespace std; int main() { string s2; cin>>s2; string s; int c=0,countv=0; cin>>s; for(int i=0;i<s.size();i++) { if(s[i]=='U') c++; else c--; if(c==0&&s[i]=='U') countv++; } cout<<countv<<endl; return 0; }