var input = require("fs").readFileSync("input.txt").toString();
var cancelled = input.replace(/!./g, "");
var garbage = [];
var match = null;
var regex = new RegExp("<([^>]*)>", "g");
do{
	match = regex.exec(cancelled);
	if(match){
		garbage.push(match[1]);
	}
}
while(match != null);
console.log(garbage.map((a)=>(a.length)).reduce((a, b)=>(a+b)));