LeetCode 119: Pascal's Triangle II

循环使用上一行相邻数值相加，需要一个中间变量储存。也可以使用公式，

class Solution {public:    vector<int> getRow(int rowIndex) {        vector<int> row;    row.push_back(1);    for (int i = 1; i <= rowIndex; ++i)    {    int t = 1, temp;    for (int j = 1; j<i; ++j)    {    temp = t;    t = row[j];    row[j] = temp + row[j];    }    row.push_back(1);    }    return row;    }};