Create 1331. Rank Transform of an Array (#601)

Author: Chayandas07

1331. Rank Transform of an Array

@@ -0,0 +1,29 @@
+// Approach - 01 [ No Sorting function]
+class Solution {
+public:
+    vector<int> arrayRankTransform(vector<int>& a) {
+        map<int,int> mp;
+        // store values in ordered map
+        for(auto& val: a){
+            mp[val]++;
+        }
+
+        // start assign value their rank 
+        // from top to bottom
+        int rank=1;
+        for(auto& val:mp){
+            val.second = rank;
+            rank++;
+        }
+
+        // traverse on array and assign them
+        // rank based on map
+        vector<int> ans(a.size());
+        for(int i=0;i<a.size();i++){
+            ans[i] = mp[a[i]];
+        }
+
+        // return the ranks
+        return ans;
+    }
+};