#include <bits/stdc++.h>
using namespace std;
int read() {
  int x = 0, flag = 1;
  char ch = getchar();
  while (!isdigit(ch)) {
    if (ch == '-') flag = -1;
    ch = getchar();
  }
  while (isdigit(ch)) {
    x = (x << 3) + (x << 1) + (ch ^ 48);
    ch = getchar();
  }
  return x * flag;
}
int n;
int s[109];
int main() {
  n = read();
  for (int i = (1), i_end_ = (n); i <= i_end_; ++i) {
    char c = getchar();
    if (c == 'U') s[i] = 1;
    if (c == 'R') s[i] = 2;
  }
  int ans = 0, i = 1;
  while (i <= n) {
    if (s[i] == 1)
      if (s[i + 1] == 2)
        ++ans, i = i + 2;
      else
        i++;
    else if (s[i] == 2)
      if (s[i + 1] == 1)
        ++ans, i = i + 2;
      else
        i++;
  }
  printf("%d\n", n - ans);
  return 0;
}
