feat:add Solution.cpp for 0117. Populating Next Right Pointers in Each Node II

Author: Stackingrule

solution/0100-0199/0117.Populating Next Right Pointers in Each Node II/Solution.cpp

@@ -0,0 +1,22 @@
+class Solution {
+public:
+    Node* connect(Node* root) {
+        if (!root) return nullptr;
+        queue<Node*> q;
+        q.push(root);
+        while (!q.empty()) {
+            int size = q.size();
+            for (int i = 0; i < size; ++i) {
+                Node* t = q.front();
+                q.pop();
+                if (i < size - 1) {
+                    t->next = q.front();
+                }
+                if (t->left) q.push(t->left);
+                if (t->right) q.push(t->right);
+            }
+        }
+
+        return root;
+    }
+};