LeetCode-Pascal's Triangle II-帕斯卡三角-DP

https://oj.leetcode.com/problems/pascals-triangle-ii/

类似DP的迭代方法，只需注意数组大小分配即可。

class Solution {
public:
    int n,m;
    vector<int> c[2];
    vector<int> getRow(int rowIndex) {
        n=rowIndex;
        c[0].resize(n+1,0);
        c[1].resize(n+1,0);
        c[0][0]=1;
        for (int i=1;i<=n;i++){
            int cur=i%2;
            int prev=(i-1)%2;
            c[cur][0]=1;
            c[cur][i]=1;
            for (int j=1;j<i;j++){
                c[cur][j]=c[prev][j-1]+c[prev][j];
            }
        }
        return c[n%2];
    }
};