蓝桥杯（3.19 刷真题）

public class Main {
	public static void main(String[] args) {
		int res = 0;
		for(int i=1;i<=100000000;i++) {
			String s = i+"";
			char[] c = s.toCharArray();
			int sum1 = 0;
			int sum2 = 0;
			if(c.length%2 == 0) {
				for(int j1=0;j1<c.length/2;j1++) {
					int jj1 = Integer.parseInt(c[j1]+"");
					sum1+=jj1;
				}
				for(int j2=c.length/2;j2<c.length;j2++) {
					int jj2 = Integer.parseInt(c[j2]+"");
					sum2+=jj2;
				}
				if(sum1 == sum2) {
					res++;
				}
			}
		}
		System.out.println(res);//4430091
	}
}

P8649 [蓝桥杯 2017 省 B] k 倍区间

import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int k = sc.nextInt();
		int[] res = new int[n+1];
		long sum = 0;
		for(int i=1;i<=n;i++) {
			res[i] = sc.nextInt();
			if(res[i]%k == 0)
				sum++;
		}
		for(int i=1;i<=n;i++) {		
			long num = res[i];
			for(int j=i+1;j<=n;j++) {
				num+=res[j];
				if(num % k == 0) {
					sum++;
				}
			}
		}
		System.out.println(sum);
	}
}