题解 | 分割等和子集

import java.util.*;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        // 注意 hasNext 和 hasNextLine 的区别
        while (in.hasNextInt()) { // 注意 while 处理多个 case
            int n = in.nextInt();
            int[] nums = new int[n];
            for (int i=0; i<n; i++) {
                nums[i] = in.nextInt();
            }
            boolean flag = process(nums, n);
            System.out.println(flag);
        }
    }


    private static boolean process(int[] nums, int n) {
        int sum = 0;
        for (int num : nums) {
            sum += num;
        }
        if (sum%2 != 0) return false;
        int target = sum / 2;
        int[] dp = new int[target+1];

        Arrays.fill(dp, Integer.MIN_VALUE);
        dp[0] = 0;
        for (int i=0; i<n; i++) {
            for (int j=target; j>=nums[i]; j--) {
                dp[j] = Math.max(dp[j], dp[j-nums[i]] + 1);
            }
        }
        return dp[target] < 0 ? false : true; 

    }
}