题目描述

package day;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class k倍区间 {

    /**
     * @param args
     * @throws IOException 
     */
    public static void main(String[] args) throws IOException {
        // TODO Auto-generated method stub
        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(System.in));
        String p[]=bufferedReader.readLine().split(" ");
        int n=Integer.parseInt(p[0]);
        int k=Integer.parseInt(p[1]);
        long a[]=new long [n+1];
        int b[]=new int [k+1];
        b[0]=1;
        for(int i=1;i<=n;i++){
            a[i]=Integer.parseInt(bufferedReader.readLine());
            a[i]+=a[i-1];
        }
        long res=0;
        for (int i = 1; i <=n; i++) {
            int c=(int) (a[i]%k);
            res+=b[c];
            b[c]++;
        }
        System.out.println(res);

    }

}