Java hashMap and ArrayList problems static HashMap Q1ArrayLi
Solution
Methods:
private static int Q2(ArrayList<ArrayList<Integer>> arls) {
int sum = 0;
for (int i = 0; i < arls.size(); i++) {
Iterator itr = arls.get(i).iterator();
while (itr.hasNext()) {
Integer ii = (int) itr.next();
sum += ii;
}
}
return sum;
}
private static HashMap<String, Integer> Q1(ArrayList<String> al) {
HashMap<String, Integer> res = new HashMap<String, Integer>();
for (int i = 0; i < al.size(); i++) {
res.put(al.get(i), new Integer(al.get(i).length()));
}
return res;
}
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Complete Program To make You understand:
HashMapArrayListDemo.java
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
public class HashMapArrayListDemo {
public static void main(String[] args) {
ArrayList<String> al = new ArrayList<String>();
al.add(\"Williams\");
al.add(\"Johnson\");
al.add(\"Kanes\");
al.add(\"Bobby\");
HashMap<String, Integer> hm = Q1(al);
Set s = hm.entrySet();
Iterator i = s.iterator();
while (i.hasNext()) {
Map.Entry m = (Map.Entry) i.next();
System.out
.println(\"Key = \" + m.getKey() + \" Value=\" + m.getValue());
}
ArrayList<Integer> arl1 = new ArrayList<Integer>();
arl1.add(3);
arl1.add(4);
arl1.add(5);
ArrayList<Integer> arl2 = new ArrayList<Integer>();
arl2.add(6);
arl2.add(7);
arl2.add(8);
ArrayList<Integer> arl3 = new ArrayList<Integer>();
arl3.add(9);
arl3.add(10);
arl3.add(11);
ArrayList<ArrayList<Integer>> arls = new ArrayList<ArrayList<Integer>>();
arls.add(arl1);
arls.add(arl2);
arls.add(arl3);
int tot = Q2(arls);
System.out.println(\"The Sum of All elements is :\" + tot);
}
private static int Q2(ArrayList<ArrayList<Integer>> arls) {
int sum = 0;
for (int i = 0; i < arls.size(); i++) {
Iterator itr = arls.get(i).iterator();
while (itr.hasNext()) {
Integer ii = (int) itr.next();
sum += ii;
}
}
return sum;
}
private static HashMap<String, Integer> Q1(ArrayList<String> al) {
HashMap<String, Integer> res = new HashMap<String, Integer>();
for (int i = 0; i < al.size(); i++) {
res.put(al.get(i), new Integer(al.get(i).length()));
}
return res;
}
}
___________________
Output:
Key = Johnson Value=7
Key = Williams Value=8
Key = Bobby Value=5
Key = Kanes Value=5
The Sum of All elements is :63
________Thank You

