120. Triangle

public class Solution {
public int minimumTotal(List<List<Integer>> triangle) {
int sum[] = new int[triangle.size()+1];
for (int i = triangle.size() - 1; i >= 0 ; i --){
for (int j = 0; j <= i; j ++){
sum[j] = Math.min(sum[j], sum[j+1]) + triangle.get(i).get(j);
}
}
return sum[0];
}
}