Submission #969811

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Source Code Expand

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.*;

public class Main {

    static BufferedReader in;
    static PrintWriter out;
    static StringTokenizer tok;

    void solve() throws IOException {
        int n = ni();
        int k = ni();
        int[] a = nia(n);

        HashMap<Integer, Integer> map = new HashMap<>();
        for (int i = 1; i * i <= k; i++) {
            if (k % i == 0) {
                map.put(i, 0);
                map.put(k / i, 0);
            }
        }

        for (int i = 0; i < n; i++) {
            int x = gcd(a[i], k);
            map.put(x, map.get(x) + 1);
        }

        Set<Integer> set = map.keySet();
        long ans = 0;
        for (int x : set) {
            for (int y : set) {
                if ((long) x * y % k == 0) {
                    if (x != y) {
                        ans += (long) map.get(x) * map.get(y);
                    } else {
                        ans += (long) (map.get(x) - 1) * map.get(x);
                    }
                }
            }
        }

        out.println(ans / 2);
    }

    int gcd(int a, int b) {
        return a == 0 ? b : gcd(b % a, a);
    }

    String ns() throws IOException {
        while (!tok.hasMoreTokens()) {
            tok = new StringTokenizer(in.readLine(), " ");
        }
        return tok.nextToken();
    }

    int ni() throws IOException {
        return Integer.parseInt(ns());
    }

    long nl() throws IOException {
        return Long.parseLong(ns());
    }

    double nd() throws IOException {
        return Double.parseDouble(ns());
    }

    String[] nsa(int n) throws IOException {
        String[] res = new String[n];
        for (int i = 0; i < n; i++) {
            res[i] = ns();
        }
        return res;
    }

    int[] nia(int n) throws IOException {
        int[] res = new int[n];
        for (int i = 0; i < n; i++) {
            res[i] = ni();
        }
        return res;
    }

    long[] nla(int n) throws IOException {
        long[] res = new long[n];
        for (int i = 0; i < n; i++) {
            res[i] = nl();
        }
        return res;
    }

    public static void main(String[] args) throws IOException {
        in = new BufferedReader(new InputStreamReader(System.in));
        out = new PrintWriter(System.out);
        tok = new StringTokenizer("");
        Main main = new Main();
        main.solve();
        out.close();
    }
}

Submission Info

Judge Result