package LeetCode;

import java.util.Arrays;

public class LC_416 {
/*    //一维dp[]
    public boolean canPartition(int[] nums) {
        int sum = Arrays.stream(nums).sum();
        if (sum % 2 != 0) return false;
        Arrays.stream(nums).sorted();
        int[] dp = new int[sum + 1];
        for (int i = 0; i < nums.length; i++) {
            for (int j = sum; j >= nums[i]; j--) {
                dp[j] = Math.max(dp[j], dp[j - nums[i]] + nums[i]);
                if (dp[j] == sum / 2) return true;
            }
        }
        return false;*/
    public static void main(String[] args) {
        canPartition(new int[]{1,2,5});
    }
    public static boolean canPartition(int[] nums) {
        int sum = Arrays.stream(nums).sum();
        if (sum % 2 != 0) return false;
        Arrays.stream(nums).sorted();
        int[][] dp = new int[nums.length+1][sum + 1];
        //在此初始化会报错  样例[1,2,5]
//        for (int i = nums[0]; i <= sum; i++) {
//            dp[0][i] = nums[0];
//        }
        for (int i = 1; i < nums.length; i++) {
            for (int j = 1; j <= sum; j++) {
                if (j < nums[i-1]) {
                    dp[i][j] = dp[i - 1][j];
                } else {
                    dp[i][j] = Math.max(dp[i - 1][j], dp[i - 1][j - nums[i - 1]] + nums[i-1]);
                    if (dp[i][j] == sum / 2) return true;
                }
            }
        }
        return false;
    }
}