119_Pascal's_Triangle

Leetcode 119: Pascal's Triangle II
Detailed video explanation: https://youtu.be/IWXZAvBIuyE
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C++:
----
class Solution {
public:
    vector<int> getRow(int rowIndex) {
        vector<int> result(rowIndex+1, 1);
        for(int i = 1; i < rowIndex; ++i){
            for(int j = i; j > 0; --j)
                result[j] += result[j-1];
        }
        return result;
    }
};


Java:
-----
class Solution {
    public List<Integer> getRow(int rowIndex) {
        List<Integer> result = new ArrayList();
        for(int i = 0; i < rowIndex+1; ++i) result.add(1);
        for(int i = 1; i < rowIndex; ++i)
            for(int j = i; j > 0; --j) result.set(j, result.get(j) + result.get(j-1));
        return result;
    }
}



Python3:
-------
class Solution:
    def getRow(self, rowIndex: int) -> List[int]:
        result = [1]*(rowIndex + 1)
        for i in range(1, rowIndex):
            for j in range(i, 0, -1):
                result[j] += result[j-1]
        return result