import java.io.*; import java.util.*; import java.util.regex.Matcher; import java.util.regex.Pattern; import java.lang.ArrayIndexOutOfBoundsException; /** * @author yoshikyoto */ class Main extends MyUtil{ public static void main(String[] args) throws Exception{ new Main().solve(); } // public static Graph g; void solve() throws Exception{ // ここからコードを書く CountHashMap map = new CountHashMap(); int n = readInt(); int[] a = readIntMap(); for(int i = 0; i < n; i++){ map.add(a[i]); } int ans = 0; for(int i : map.keySet()){ if(map.get(i) == 1) ans++; } System.out.println(ans); } } class ArrayComp implements Comparator{ public int compare(int[] a, int[] b){ int l = Math.min(a.length, b.length); for(int i = 0; i < l; i++){ if(a[i] == b[i]) continue; return a[i] - b[i]; } return 0; } } class Node extends ArrayList{ int index, depth = -1, dist = -1; Node(int index){this.index = index;} Node parent; boolean visited = false; } class Edge{ int from, to, cost; Edge(int from, int to, int cost){ this.from = from; this.to = to; this.cost = cost; } } class NodeComparator implements Comparator{ public int compare(Node a, Node b){ return a.dist - b.dist; } } class Graph{ Node n[]; Graph(int node_count){ n = new Node[node_count]; for(int i = 0; i < node_count; i++) n[i] = new Node(i); } public void add(Edge e){ n[e.from].add(e); } public Node get(int i){return n[i];} public Node lca(int a, int b){ // 浅い方をaとする Node nodeA, nodeB; if(n[a].depth < n[b].depth){ nodeA = n[a]; nodeB = n[b]; }else{ nodeA = n[b]; nodeB = n[a]; } // 同じ深さまで親をたどる int diff = nodeB.depth - nodeA.depth; for(int k = 0; k < diff; k++){ nodeB = nodeB.parent; } // 共通祖先を見つける while(nodeA != nodeB){ nodeA = nodeA.parent; nodeB = nodeB.parent; } return nodeA; } public void calcDepth(int root){ ArrayDeque que = new ArrayDeque(); que.push(root); n[root].depth = 0; while(que.size() > 0){ int curr = que.pop(); Node curr_node = n[curr]; for(Edge e : curr_node){ int next = e.to; Node next_node = n[next]; if(next_node.depth == -1){ next_node.depth = curr_node.depth + 1; next_node.parent = curr_node; que.push(next); } } } } public int[] dijkstra(int s){ PriorityQueue q = new PriorityQueue(n.length, new NodeComparator()); Node start_node = new Node(s); start_node.dist = 0; q.add(start_node); int[] dist = new int[n.length]; for (int i = 0; i < dist.length; i++) dist[i] = -1; dist[s] = 0; while(q.size() > 0){ Node currNode = q.poll(); if(dist[currNode.index] < currNode.dist) continue; for(Edge e : n[currNode.index]){ Node nextNode = new Node(e.to); nextNode.dist = currNode.dist + e.cost; if(dist[e.to] == -1 || dist[e.to] > nextNode.dist){ dist[e.to] = nextNode.dist; q.add(nextNode); } } } return dist; } } class Regex{ Pattern p; Matcher m; String str; Regex(String regex_str){p = Pattern.compile(regex_str);} void setStr(String str){m = p.matcher(str);} boolean find(){return m.find();} String group(int i){return m.group(i);} String group(){return m.group();} } /** * UnionFindTree * @author yoshikyoto */ class UnionFindTree{ public int[] parent, rank; public int n; public int count; // 初期化 UnionFindTree(int n){ this.n = n; count = n; parent = new int[n]; rank = new int[n]; for(int i = 0; i < n; i++){ parent[i] = i; rank[i] = 0; } } // 根を求める int find(int x){ if(parent[x] == x){ return x; }else{ return parent[x] = find(parent[x]); } } // xとyの集合を結合 void unite(int x, int y){ x = find(x); y = find(y); if(x == y){ return; } if(rank[x] < rank[y]){ parent[x] = y; count--; }else{ parent[y] = x; if(rank[x] == rank[y]) rank[x]++; count--; } } // xとyが同じ集合か boolean same(int x, int y){ return find(x) == find(y); } }; /** * 整数を数え上げたりするクラス * new Prime(int n) でnまでエラトステネスの篩を実行。 * @author yoshikyoto * @param a[i] iが素数の時true * @param count[i] i以下の素数の数 */ class Prime{ boolean[] a; int[] count; int[] primacity; Prime(int n){ a = new boolean[n+1]; primacity = new int[n+1]; a[0] = false; a[1] = false; for(int i = 2; i <= n; i++) a[i] = true; // ふるい for(int i = 2; i < (n - 3) / 2; i++){ if(a[i]){ primacity[i] = 1; for(int j = 2; j * i <= n; j++){ a[j * i] = false; primacity[j * i]++; } } } // 数え上げ count = new int[n+1]; count[0] = 0; for(int i = 1; i <= n; i++){ int gain = 0; if(a[i]) gain = 1; count[i] = count[i-1] + gain; } } boolean isPrime(int i){return a[i];} static boolean calcPrime(int i){ if(i <= 1) return false; if(i == 2) return true; if(i % 2 == 0) return false; for(int j = 3; j <= Math.sqrt(i); j+=2){ if(i % j == 0) return false; } return true; } } class CountHashMap extends HashMap{ ArrayList keyArray = new ArrayList(); public void add(E key){add(key, 1);} public void add(E key, Integer value){ if(containsKey(key)){value += get(key); }else{keyArray.add(key);} put(key, value); } } /** * MyUtil * @author yoshikyoto */ class MyUtil extends MyIO{ public static Random rand = new Random(); public static int digit(int n){return String.valueOf(n).length();} public static String reverse(String s){return (new StringBuffer(s)).reverse().toString();} public static void dsort(int[] a){ Arrays.sort(a); int l = a.length; for(int i = 0; i < l/2; i++){ int tmp = a[i]; a[i] = a[l-1-i]; a[l-1-i] = tmp; } } public static void sleep(int t){try{Thread.sleep(t);}catch(Exception e){}} public static int sum(int[] a){int s = 0; for(int i = 0; i < a.length; i++)s+=a[i]; return s;} public static int[] cp(int[] a){ int[] b = new int[a.length]; for(int i = 0; i < a.length; i++) b[i] = a[i]; return b; } public static int randomInt(int min, int max){return min + rand.nextInt(max - min + 1);} static boolean inside(int y, int x, int h, int w){return 0 <= y && y <= (h-1) && 0 <= x && x <= (w-1);}; public static boolean isUpper(char c){return 'A'<=c&&c<='Z';} public static boolean isLower(char c){return 'a'<=c&&c<='z';} public static char toUpper(char c){ if(isLower(c)) return (char)(c - 'a' + 'A'); return c; } public static char toLower(char c){ if(isUpper(c)) return (char)(c - 'A' + 'a'); return c; } public static int[] swap(int[] arr, int i, int j){ int[] ret = cp(arr); int tmp = ret[i]; ret[i] = ret[j]; ret[j] = tmp; return ret; } public static int toInt(boolean[] a){ int pow = 1, ret = 0, l = a.length; for(int i = 0; i < l; i++){ if(a[i]) ret += pow; pow *= 2; } return ret; } } /** * MyIO * @author yoshikyoto */ class MyIO extends MyMath{ static Scanner sc = new Scanner(new InputStreamReader(System.in)); public static char scNextChar(){return sc.next().charAt(0);} static BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); public static String line; public static int ins[]; public static int[] readIntMap() throws IOException{return parseInt(readLine().split(" "));} public static int readIntMap(int i) throws Exception{ if(i == 0) ins = readIntMap(); return ins[i]; } public static int[][] readIntMap(int n, int m) throws IOException{ int[][] ret = new int[n][]; for(int i = 0; i < n; i++) ret[i] = readIntMap(); return ret; } public static int[] readIntToMap(int n) throws IOException{ int[] ret = new int[n]; for(int i = 0; i < n; i++) ret[i] = readInt(); return ret; } public static int[] readNoDistIntMap() throws IOException{ String[] strs = readLine().split(""); int l = strs.length; int[] ret = new int[l-1]; for(int i = 1; i < l; i++) ret[i-1] = parseInt(strs[i]); return ret; } public static boolean readToLine() throws IOException{return (line = br.readLine()) != null;} public static String readLine() throws IOException{return br.readLine();} public static int readInt() throws IOException{return Integer.parseInt(br.readLine());} public static int[] parseInt(String[] arr){ int[] res = new int[arr.length]; for(int i = 0; i < arr.length; i++)res[i] = Integer.parseInt(arr[i]); return res; } public static double[] parseDouble(String[] arr){ double[] res = new double[arr.length]; for(int i = 0; i < arr.length; i++)res[i] = Double.parseDouble(arr[i]); return res; } public static boolean[] parseBool(String[] arr){ int[] t = parseInt(arr); boolean[] res = new boolean[t.length]; for(int i = 0; i < t.length; i++){ if(t[i] == 1){res[i] = true; }else{res[i] = false;} } return res; } public static int parseInt(Object o){return Integer.parseInt(o.toString());} } class MyMath{ public static int max(int[] arr){return max(arr, 0, arr.length-1);} public static int max(int[] arr, int l, int r){ int max = arr[l]; for(int i = l+1; i <= r; i++) max = Math.max(max, arr[i]); return max; } public static int min(int[] arr){return min(arr, 0, arr.length-1);} public static int min(int[] arr, int l, int r){ int min = arr[l]; for(int i = l+1; i <= r; i++) min = Math.min(min, arr[i]); return min; } public static boolean isCross(int x1, int y1, int x2, int y2, int x3, int y3, int x4, int y4){ // 並行な場合 int m = (x2-x1)*(y4-y3)-(y2-y1)*(x4-x3); if(m == 0) return false; // 媒介変数の値が0より大きく1以下なら交差する、これは問題の状況によって変わるかも。 double r =(double)((y4-y3)*(x3-x1)-(x4-x3)*(y3-y1))/m; double s =(double)((y2-y1)*(x3-x1)-(x2-x1)*(y3-y1))/m; return (0 < r && r <= 1 && 0 < s && s <= 1); } public static boolean isParallel(int x1, int y1, int x2, int y2, int x3, int y3, int x4, int y4){ if((x2-x1)*(y4-y3) == (y2-y1)*(x4-x3)) return true; else return false; } public static double sq(double d){return d*d;} public static int sq(int i){return i*i;} public static int sqdist(int x1, int y1, int x2, int y2){return (x1-x2) + sq(y1-y2);} public static double sqdist(double x1, double y1, double x2, double y2){return sq(x1-x2) + sq(y1-y2);} public static double dist(int x1, int y1, int x2, int y2){return Math.sqrt(sqdist(x1, y1, x2, y2));} public static double dist(double x1, double y1, double x2, double y2){return Math.sqrt(sqdist(x1, y1, x2, y2));} long comb(long n, long m){ if(n < m) return 0; long c = 1; m = (n - m < m ? n - m : m); for(long ns = n - m + 1, ms = 1; ms <= m; ns ++, ms ++){c *= ns; c /= ms;} return c; } static int gcd(int a, int b){if(a%b==0){return(b);}else{return(gcd(b,a%b));}}; /** * aの中から、合計がborderを超えるペア(重複除く)の数を数える */ static int countPair(int[] a, int border){ int count = 0, l = a.length, i = 0, j = l-1; for (; i < l; i++) { for (; j >= 0; j--) if(a[i] + a[j] <= border) break; count += l - (j + 1); if(j < i) count--; } return count/2; } // modに対応したDPのCombination int mcomb(int n, int m, int mod){ n = n - m; int[][] dp = new int[n+1][m+1]; for(int i = 0; i <= n; i++) dp[i][0] = 1; for(int i = 0; i <= m; i++) dp[0][i] = 1; // mod = 0 の時は余りを取らない if(mod != 0){ for(int i = 1; i <= n; i++){ for(int j = 1; j <= m; j++){ dp[i][j] = (dp[i-1][j] + dp[i][j-1]); } } // それ以外の時は mod をとっていく }else{ for(int i = 1; i <= n; i++){ for(int j = 1; j <= m; j++){ dp[i][j] = (dp[i-1][j] + dp[i][j-1]) % mod; } } } return dp[n][m]; } }