function Main(input) {
	var str = input;
	var a = [];
	var n = str.split('\n');
	var x  =Number(n[0]);
	var ans = 0;
	n.shift();
  	a = n;
	//console.log(a);
	var b = Array.from(new Set(a));
 	ans = b.length;
 	console.log(ans);
 }
//*おまじない
Main(require("fs").readFileSync("/dev/stdin", "utf8"));