process.stdin.resume();
process.stdin.setEncoding('utf8');


function Main(input) {
    var inputs = input.split("\n").filter((e, i) => i !== 0).map(e => parseInt(e)).sort((a, b) => a - b).filter((e, i, a) => a.indexOf(e) == i);
    console.log(inputs.length);
}

Main(require("fs").readFileSync("/dev/stdin", "utf8"));