Pascal's triangle II

Given a non-negative index k where k ≤ 33, return the kth index row of the Pascal's triangle.

Note that the row index starts from 0.

In Pascal's triangle, each number is the sum of the two numbers directly above it.

Example:

Input: 3 Output: [1,3,3,1]

Solution: Modify in place

vector<int> getRow(int rowIndex) {
    vector<int> ans(rowIndex+1, 0);
    ans[0] = 1;
    for (int i = 0; i<=rowIndex; i++) {
        for (int j=i; j>0; j--) {
            ans[j] += ans[j-1];
        }
    }
    return ans;
}