1st javascript task

Task1.js

@@ -0,0 +1,30 @@
+function GroupByKey(array,key)
+{
+  const tempData = {};
+
+  for ( var index=0; index<array.length; index++)
+   {
+
+    if (!tempData[array[index][key]]) 
+    {
+        tempData[array[index][key]]=[];
+    }
+
+    tempData[array[index][key]].push(array[index])
+
+  }
+  return tempData
+}
+const array=[
+    {id:1,name:"Bilal", city:"Lahore"},
+    {id:1,name:"Bilal", city:"Lahore"},
+    {id:3,name:"Hafsa", city:"Karachi"},
+    {id:4,name:"Rehan", city:"Lahore"},
+    {id:5,name:"Saqib", city:"Karachi"},
+    {id:6,name:"Farhan", city:"Islamabad"}
+
+];
+
+const key='city';
+
+console.log(GroupByKey(array,key))

Task2.js

@@ -0,0 +1,25 @@
+const array=[
+    {id:1,name:"Bilal", city:"Lahore"},
+    {id:1,name:"Bilal", city:"Lahore"},
+    {id:3,name:"Hafsa", city:"Karachi"},
+    {id:4,name:"Rehan", city:"Lahore"},
+    {id:5,name:"Saqib", city:"Karachi"},
+    {id:6,name:"Farhan", city:"Islamabad"}
+];
+const key='city';
+
+function GroupByKey(arr,key) {
+    var tempobj=[];
+    arr.reduce((accumulator,currentvalue)=>{
+        if(!accumulator[currentvalue[key]]){
+            accumulator[currentvalue[key]]=[]
+        }
+        accumulator[currentvalue[key]].push(currentvalue)
+        tempobj=accumulator
+        return accumulator
+    },{});
+    return tempobj
+
+}
+
+console.log(GroupByKey(array,key))