代码:
class Solution {
public:
/**
* @param triangle: a list of lists of integers.
* @return: An integer, minimum path sum.
*/
int minimumTotal(vector<vector<int> > &triangle) {
// write your code here
const int len = triangle.size();
vector<vector<int>> buff(len, vector<int>(len));
buff[0][0] = triangle[0][0];
for (int i = 1; i < len; i++)
{
for (int j = 0; j <= i; j++)
{
// 要取buff[i-1][j-1],和buff[i-1][j],但是要保证不越界。
// 第i-1行的j的取值范围为[0, i-1]
int lo = max(0, j-1);
int hi = min(j, i-1);
buff[i][j] = min(buff[i-1][lo], buff[i-1][hi]) + triangle[i][j];
}
}
int res = buff[len-1][0];
for (int i = 1; i < len; i++)
res = min(res, buff[len-1][i]);
return res;
}
};
lintcode截图: