Pascal's Triangle

Leetcode-118.cpp

class Solution {
public:
    vector<vector<int>> generate(int numRows) {
        vector<vector<int>> res(numRows);

        for (int i = 0; i < numRows; i++) {
            res[i] = vector<int>(i + 1, 1);

            for (int j = 1; j < i; j++) {
                res[i][j] = res[i-1][j]+ res[i-1][j-1];
            }
        }
        return res;
    }
};