const stdin=require("fs").readFileSync("/dev/stdin", "utf8");
const argv=stdin.split("\n");
const total=Number(argv[0]);
const mochies=argv.slice(1).map(a=>Number(a));

mochies.sort((a,b)=>a-b).filter((a,idx,self)=>self.indexOf(a)==idx);

console.log(mochies.length);