HashMap<String, Integer> map = new HashMap<>();

Week 3: Objects, files and exceptions/11b. Combine names and grades

@@ -0,0 +1,110 @@
+Write the method
+
+public static HashMap<String, Integer> combine(ArrayList<String> names, ArrayList<Integer> grades)
+
+which takes a list of names and grades as parameters. 
+Create and return a new hashmap of names and grades, with names as keys and grades as values. 
+The names and grades are listed at the corresponding indexes (i.e., the first name and the first grade belong together).
+
+
+
+
+Example execution:
+
+public static void main(String[] args){
+    ArrayList<String> names = new ArrayList<>();
+    ArrayList<Integer> grades = new ArrayList<>();
+
+    names.add("Axel");
+    names.add("Ann");
+    names.add("Michael");
+
+    grades.add(9);
+    grades.add(8);
+    grades.add(10);
+
+    HashMap<String, Integer> hm = combine(names, grades);
+    System.out.println(hm);
+}
+
+Program outputs:
+{Axel=9, Michael=10, Ann=8}
+
+
+
+==========================================================
+
+
+
+
+
+
+import java.util.Random;
+import java.util.ArrayList;
+import java.util.HashMap;
+
+public class Test{
+    public static void main(String[] args){
+        final Random r = new Random();
+        
+        
+        String[] nn = "Jack Joseph Lisa Lena Maya Kim".split(" ");
+        
+        ArrayList<String> nimet = new ArrayList<>();
+        ArrayList<Integer> arvosanat = new ArrayList<>();
+        
+        for (String nimi : nn) {
+            nimet.add(nimi);
+            arvosanat.add(r.nextInt(7) + 4);
+        }
+        
+        System.out.println("Names: " + nimet);
+        System.out.println("Grades: " + arvosanat);
+        System.out.println("Combined: ");
+        
+        HashMap<String, Integer> taulu = combine(nimet, arvosanat);
+        
+        for (String nimi : nimet) {
+            System.out.println(nimi + ": " + taulu.get(nimi));
+        }
+        
+    }
+
+
+
+
+
+
+    public static HashMap<String, Integer> combine(ArrayList<String> names, ArrayList<Integer> grades) {
+        HashMap<String, Integer> map = new HashMap<>();
+        for (int i = 0; i < names.size(); i++) {
+            map.put(names.get(i), grades.get(i));
+        }
+        return map;
+    }
+
+
+
+
+
+}
+
+
+
+
+
+
+Names: [Jack, Joseph, Lisa, Lena, Maya, Kim]
+Grades: [4, 4, 8, 8, 8, 7]
+Combined: 
+Jack: 4
+Joseph: 4
+Lisa: 8
+Lena: 8
+Maya: 8
+Kim: 7
+
+
+ 
+
+