LeetCode Q119: Pascal's Triangle II

Given an index k, return the kth row of the Pascal's triangle.

For example, given k = 3,
Return [1,3,3,1].

Note:
Could you optimize your algorithm to use only O(k) extra space?

	class Solution {
	public:
	vector<int> getRow(int numRows) {
	numRows++;
	vector<int> newRow;
	vector<int> lastRow;
	for(int i=1; i<=numRows; i++){
	for(int j=1; j<=i;){
	if(j==1||j==i){
	newRow.push_back(1);
	j++;
	}
	else
	for(int k=0; k<lastRow.size()-1; ++k, ++j)
	newRow.push_back(lastRow[k]+lastRow[k+1]);
	}
	lastRow=newRow;
	newRow.clear();
	}
	return lastRow;
	}
	};

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