import std.stdio, std.conv, std.string, std.array, std.range, std.algorithm, std.container;
import std.math, std.random, std.bigint, std.datetime, std.format;
void main(string[] args){ if(args.length > 1) if(args[1] == "-debug") DEBUG = 1; solve(); }
void log()(){ writeln(""); } void log(T, A ...)(T t, lazy A a){ if(DEBUG) write(t, " "), log(a); } bool DEBUG = 0; 
string read(){ static string[] ss; while(!ss.length) ss = readln.chomp.split; string res = ss[0]; ss.popFront; return res; }
// ----- ----- ----- ----- ----- ----- ----- ----- ----- ----- ----- ----- //

void solve(){
	string s = readln.chomp;
	
	long ans;
	string old = "", now = "";
	foreach(c; s){
		now ~= c;
		if(now != old){
			ans += 1;
			old = "" ~ now;
			now = "";
		}
		log("old:", old, "now:", now, "ans:", ans);
	}

	ans.writeln;

}

/*
	long n = read.to!long;
	long m = read.to!long;
	long k = read.to!long;

	long a = read.to!long;
	long b = read.to!long;
	
	long x = read.to!long;
	long y = read.to!long;
	long z = read.to!long;

	long[] as;
	foreach(i; 0 .. n) as ~= read.to!long;

	long[] bs;
	foreach(i; 0 .. n) bs ~= read.to!long;

	long[] as;
	foreach(j; 0 .. m) as ~= read.to!long;

	long[] bs;
	foreach(j; 0 .. m) bs ~= read.to!long;
	
	struct S{
		long a, b;
	}
	S[] xs;
	foreach(i; 0 .. n) xs ~= S(read.to!long, read.to!long);

*/
