119. Pascal's Triangle II

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Given an integer rowIndex, returns the rowIndexth (indexed 0) row of Pascal's triangle. In Pascal's triangle, each number is the sum of the two numbers directly above it, as shown: Example 1: Input: rowIndex = 3 Output: [1,3,3,1] Example 2: Input: rowIndex = 0 Output: [1] Example 3: Input: rowIndex = 1 Output: [1,1] 0 <= rowIndex <= 33 Solution class Solution { public: vector getRow(int rowIndex) { vector> ans; ans.push_back({1}); for(int i = 1 ; i < rowIndex + 1; i++) { vector level(i); level[0] = 1; ans.push_back(level); for(int j = 1; j < i; j++) { if(j == 0) ans[i][j] = 1; else ans[i][j] = ans[i - 1][j] + ans[i - 1][j - 1]; } ans[i].push_back(1); } return ans[rowIndex]; } };

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