Problem:
Score : 200 points

Problem Statement

An X-layered kagami mochi (X ≥ 1) is a pile of X round mochi (rice cake) stacked vertically where each mochi (except the bottom one) has a smaller diameter than that of the mochi directly below it. For example, if you stack three mochi with diameters of 10, 8 and 6 centimeters from bottom to top in this order, you have a 3-layered kagami mochi; if you put just one mochi, you have a 1-layered kagami mochi.

Lunlun the dachshund has N round mochi, and the diameter of the i-th mochi is d_i centimeters. When we make a kagami mochi using some or all of them, at most how many layers can our kagami mochi have?

Constraints

1 ≤ N ≤ 100

1 ≤ d_i ≤ 100

All input values are integers.

Input

Input is given from Standard Input in the following format:

N
d_1
:
d_N

Output

Print the maximum number of layers in a kagami mochi that can be made.

Sample Input 1

4
10
8
8
6

Sample Output 1

3

If we stack the mochi with diameters of 10, 8 and 6 centimeters from bottom to top in this order, we have a 3-layered kagami mochi, which is the maximum number of layers.

Sample Input 2

3
15
15
15

Sample Output 2

1

When all the mochi have the same diameter, we can only have a 1-layered kagami mochi.

Sample Input 3

7
50
30
50
100
50
80
30

Sample Output 3

4

Solution in JavaScript (node.js v5.12) (judge verdict: Accepted)

"use strict";

var input = require("fs").readFileSync("/dev/stdin", "utf8");
var cin = input.split(/ |\n/),
    cid = 0;

function next() {
    return +cin[cid++];
} // number一個取得
function nextstr() {
    return cin[cid++];
} // 文字列一個取得
function nextbig() {
    return BigInt(cin[cid++]);
} // BigInteger一個取得
// 長さnの配列として取得。aは文字列フラグ
function nexts(n, a) {
    return a ? cin.slice(cid, cid += n) : cin.slice(cid, cid += n).map(a => +a);
}
// 長さnのBigInt配列として取得。
function nextsbig(n) {
    return cin.slice(cid, cid += n).map(a => BigInt(a));
}
// w個ずつを組にして長さhの配列。aは文字列フラグ。
function nextm(h, w, a) {
    var r = [],
        i = 0;
    if (a)
        for (; i < h; i++) r.push(cin.slice(cid, cid += w));
    else
        for (; i < h; i++) r.push(cin.slice(cid, cid += w).map(a => +a));
    return r;
}
// 多次元配列。v,a1,a2,a3 なら、3次元。[[値vで長さa3の配列]をa2個並べた配列]をa1個並べた配列。
function xArray(v) {
    var a = arguments,
        l = a.length,
        r = "Array(a[" + --l + "]).fill().map(x=>{return " + v + ";})";
    while (--l) r = "Array(a[" + l + "]).fill().map(x=>" + r + ")";
    return eval(r);
}


console.log(main().toString());

function main() {
    let n = next(); //("00000" + nexts()).substr(-5).split("").map(x => +x);
    let a = new Set(nexts(n))
    let ans = a.size

    return ans;
}