adding a pq problem

leetcode/p215_kth_largest_element.cpp

@@ -0,0 +1,19 @@
+class Solution {
+public:
+    int findKthLargest(vector<int>& nums, int k) {
+        int ans;
+        int size = nums.size();
+        std::priority_queue<int> pq;
+        for(int i=0;i<size;i++){
+            // maintain a max heap
+            pq.push(nums[i]);
+        }
+        while(k>1){
+            // pop out k-1 times
+            pq.pop();
+            k--;
+        }
+        ans = pq.top();
+        return ans;
+    }
+};