【数组】Triangle

题目：

Given a triangle, find the minimum path sum from top to bottom. Each step you may move to adjacent numbers on the row below.

For example, given the following triangle

[
     [2],
    [3,4],
   [6,5,7],
  [4,1,8,3]
]

The minimum path sum from top to bottom is 11 (i.e., 2 + 3 + 5 + 1 = 11).

思路：

方法一：从上到下， 下一行的结果根据上一行的路径累计和而计算。 
triangle[i][j] += min(triangle[i -1 [j -1 ],triangle[i -1 ][j ] ) ，这样需要处理j=0和j=最大值。
方法二：从下往上，每一行的结果根据下面一行的路基累计和而计算。（参考大神才晓得） 
triangle[i][j] += min(triangle[i + 1][j], triangle[i + 1][j + 1])

/**
 * @param {number[][]} triangle
 * @return {number}
 */
var minimumTotal = function(triangle) {
    for(var i=triangle.length-2;i>=0;i--){
        for(var j=0;j<i+1;j++){
            if(triangle[i+1][j]>triangle[i+1][j+1]){
                triangle[i][j]+=triangle[i+1][j+1]
            }else{
                triangle[i][j]+=triangle[i+1][j]
            }
        }
    }

    return triangle[0][0];
};