118. Pascal's Triangle [Leetcode][C++]

class Solution { public: vector<vector<int>> generate(int numRows) { // Brute Force Solution Time O(N^2) & Auxiliary Space O(1) vector<vector<int>> ret(numRows); for (int i = 0; i < numRows; i++) { ret[i].resize(i+1); // Resize number of elements in each row from from numRows to i+1  ret[i][0]=1; ret[i][i]=1; // Put 1's at first & last element of each row for (int j = 1; j < i; j++) { // Assigning element values in row from second element to second last element // by adding corresponding jth & (j-1)th element in previous row // as shown in question animation ret[i][j] = ret[i - 1][j] + ret[i - 1][j - 1]; } } return ret; } };