Merge pull request #1951 from laitooo/0118-pascals-triangle.dart

Create: 0118-Pascals-Triangle.dart

Author: tahsintunan

dart/0118-pascals-triangle.dart

@@ -0,0 +1,21 @@
+class Solution {
+  List<List<int>> generate(int numRows) {
+      if (numRows == 1) {
+          return [[1]];
+      }
+
+      List<List<int>> res = [[1], [1, 1]];
+      for (int i=2; i<numRows; i++) {
+          List<int> tmp = [];
+          for (int j=0; j<i+1; j++) {
+              if (j == 0 || j == i) {
+                  tmp.add(1);
+              } else {
+                  tmp.add(res[i - 1][j - 1] + res[i - 1][j]);
+              }
+          }
+          res.add(tmp);
+      }
+      return res;
+  }
+}