'Pascal's Triangle II' soln

Author: joewnga

README.md

@@ -125,7 +125,7 @@ Note: Some solutions have multiple approaches implemented
 | x117 | [Populating Next Right Pointers in Each Node II](https://leetcode.com/problems/populating-next-right-pointers-in-each-node-ii/) | [Solution](./leetcode/populating_next_right_pointers_ii.rs) | Medium |
 | 118 | [Pascal's Triangle](https://leetcode.com/problems/pascals-triangle/) | [Solution](./leetcode/pascals_triangle.rs) | Easy |
 | 119 | [Pascal's Triangle II](https://leetcode.com/problems/pascals-triangle-ii/) | [Solution](./leetcode/pascals_triangle_ii.rs) | Easy |
-| 120 | [Triangle](https://leetcode.com/problems/triangle/) | [Solution](./leetcode/triangle.rs) | Medium |
+| >120 | [Triangle](https://leetcode.com/problems/triangle/) | [Solution](./leetcode/triangle.rs) | Medium |
 | 121 | [Best Time to Buy and Sell Stock](https://leetcode.com/problems/best-time-to-buy-and-sell-stock/) | [Solution](./leetcode/best_time_to_buy_and_sell_stock.rs) | Easy |
 | 122 | [Best Time to Buy and Sell Stock II](https://leetcode.com/problems/best-time-to-buy-and-sell-stock-ii/) | [Solution](./leetcode/best_time_to_buy_and_sell_stock_ii.rs) | Medium |
 | 123 | [Best Time to Buy and Sell Stock III](https://leetcode.com/problems/best-time-to-buy-and-sell-stock-iii/) | [Solution](./leetcode/best_time_to_buy_and_sell_stock_iii.rs) | Hard |

leetcode/pascals_triangle_ii.rs

@@ -0,0 +1,50 @@
+/// 
+/// Problem: Pascal's Triangle II
+/// 
+/// Given an integer rowIndex, return the rowIndex^th (0-indexed) row of Pascal's triangle.
+/// 
+/// In Pascal's triangle, each number is the sum of the two numbers directly above it.
+/// 
+/// 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]
+/// 
+/// Constraints:
+/// 0 <= rowIndex <= 33
+/// 
+/// Follow up: Could you optimize your algorithm to use only O(rowIndex) extra space?
+/// 
+
+// # Solution:
+// Time complexity: O(rowIndex²) 
+// Space complexity: O(rowIndex)
+
+impl Solution {
+    pub fn get_row(row_index: i32) -> Vec<i32> {
+        let row_index = row_index as usize;
+       let mut row = vec![1];
+    
+       for i in 0..row_index {
+           let mut next_row = vec![1];
+           
+           
+           for j in 0..row.len() - 1 {
+               next_row.push(row[j] + row[j + 1]);
+           }
+           
+           next_row.push(1);
+           
+           row = next_row;
+       }
+       
+       row
+    }
+}