leetcode/solution/0100-0199/0120.Triangle/Solution2.java

class Solution {
    public int minimumTotal(List<List<Integer>> triangle) {
        for (int i = triangle.size() - 2; i >= 0; --i) {
            for (int j = 0; j <= i; ++j) {
                int x = triangle.get(i).get(j);
                int y = Math.min(triangle.get(i + 1).get(j), triangle.get(i + 1).get(j + 1));
                triangle.get(i).set(j, x + y);
            }
        }
        return triangle.get(0).get(0);
    }
}