Interview Question

Q: Find the count of students who have failed (average < 50) and who have passed with distinction (average > 80)

input ->
[
[“Michael”, “70”],
[“Adam”, “85”]
[“George”, “80”]
[“Silva”, “71”]
[“George”, “37”]
[“Michael”, “21”]
]

output ->
total = 4
failed = 1
distinction = 1

public class Demo {
 public static void main(String[] args) {
  String[][] data = new String[][] { { "Michael", "70" }, { "Adam", "85" }, { "George", "80" }, { "Silva", "71" },
    { "George", "37" }, { "Michael", "21" } };

  Map<String, List<String>> map = new HashMap<>();

  for (int i = 0; i < data.length; i++) {
   String[] names = data[i];
   if (!map.containsKey(names[0])) {
    map.put(names[0], Arrays.asList(names[1]));
   } else {
    List<String> values = new ArrayList<>();
    values.addAll(map.get(names[0]));
    values.addAll(Arrays.asList(names[1]));
    map.put(names[0], values);
   }
  }

  long count = map.entrySet().stream().count();
  System.out.println("Total Candidate : "+ count);
  for (Entry<String, List<String>> entry : map.entrySet()) {
      Long x = evalute(entry.getValue());
      if(x < 50)
       System.out.println(entry.getKey() +" has failed");
      
      if(x > 80)
       System.out.println(entry.getKey() +" has distinction");
  }
 }

 private static Long evalute(List<String> list) {
  return (long) list.stream().mapToLong(Long::parseLong).average().getAsDouble();
 }
}