How to Find the Minimum Value in a Map

Get minvalue of a Map(Key,Double)

You can use the standard Collections#min() for this.

Map<String, Double> map = new HashMap<String, Double>();
map.put("1.1", 1.1);
map.put("0.1", 0.1);
map.put("2.1", 2.1);

Double min = Collections.min(map.values());
System.out.println(min); // 0.1

Update: since you need the key as well, well, I don't see ways in Collections or Google Collections2 API since a Map is not a Collection. The Maps#filterEntries() is also not really useful, since you only know the actual result at end of iteration.

Most straightforward solution would then be this:

Entry<String, Double> min = null;
for (Entry<String, Double> entry : map.entrySet()) {
    if (min == null || min.getValue() > entry.getValue()) {
        min = entry;
    }
}

System.out.println(min.getKey()); // 0.1

(nullcheck on min left aside)

How can I find the minimum value in a map?

You have a few options. The "best" way to do this is with a functor, this is guaranteed to be the fastest to call:

typedef std::pair<std::string, int> MyPairType;
struct CompareSecond
{
    bool operator()(const MyPairType& left, const MyPairType& right) const
    {
        return left.second < right.second;
    }
};

int MyClass::getMin(std::map<std::string, int> mymap) 
{
  std::pair<std::string, int> min 
      = *min_element(mymap.begin(), mymap.end(), CompareSecond());
  return min.second; 
}

(You can also nest the CompareSecond class inside MyClass.

With the code you have now, you can easily modify it to work, however. Just make the function static and use the correct syntax:

static bool 
MyClass::compare(std::pair<std::string, int> i, std::pair<std::string, int> j) 
{ 
  return i.second < j.second; 
}

int MyClass::getMin(std::map<std::string, int> mymap) 
{
  std::pair<std::string, int> min = *min_element(mymap.begin(), mymap.end(), 
                                                 &MyClass::compare);
  return min.second; 
}

Find minimum value in a map java

Simple java8 solution for map Map<Object,Integer> map = new HashMap<>();

map.values().stream().min(Integer::compare).get();

Edit
As @Andreas pointed out, there was request for using comparator, so this is solution for Java 8 which finds smallest value

public static <K, V> V min8(Map<K, V> map, Comparator<V> comp) {
    return map.values().stream().min(comp).get();
}

and this is solution for Java 7 for finding entry with smallest value

public static <K, V> Entry<K, V> min(Map<K, V> map, Comparator<V> comp) {
        Iterator<Entry<K, V>> entries = map.entrySet().iterator();
        if (!entries.hasNext()) {
            return null;
        }
        Entry<K, V> min;
        for (min = entries.next(); entries.hasNext();) {
            Entry<K, V> value = entries.next();
            if (comp.compare(value.getValue(), min.getValue()) < 0) {
                min = value;
            }
        }
        return min;
    }

my initial solution was very close to @Andreas, so i decide to change and use for loop with itterator.

Find the Min of Max values in a MapString, ListInteger without relying on for loops

You can use the methods Collections.min and Collections.max

HashMap<String, List<Integer>> myMap = new HashMap<>();

Integer min = Collections.min(myMap.values().stream().map(Collections::max).collect(Collectors.toList()));

Finding first, second, third minimum in hash map

Not quite understood second part about repeat, anyway it may help:

 public static void main(String[] args) {
        Map<Integer, Integer> map = new HashMap<>();
        map.put(1,10);
        map.put(2,100);
        map.put(3,20);
        map.put(4,990);

        Map.Entry<Integer, Integer> integerIntegerEntry = map.entrySet()
                .stream().min(Comparator.comparing(Map.Entry::getKey))
                .orElseThrow(() ->new RuntimeException("Oops!"));
        System.out.println("min val is :" + integerIntegerEntry.getValue());
        anotherMethod(integerIntegerEntry.getKey());
    }

How to find the lowest value in a HashMap

In your loop, compare the value to the current smallest and remember the smallest:

Integer smallestValue = Integer.MAX_VALUE;
String smallestKey;
for (HashMap.Entry<String, Integer> entry : itemTime.entrySet()) {
    if (entry.getValue() < smallestValue) {
        smallestKey = entry.getKey();
        smallestValue = entry.getValue();
    }
    System.out.println(entry.getKey() + " " + entry.getValue());
}
System.out.pintln("Smallest is " + smallestKey + " with " + smallestValue);

Getting min value from a hashmap which stores a object as value

You can create a Comparator that sorts based on area and get the Entry from Map

Comparator<Map.Entry<String, Country>> comp = 
         Comparator.comparing((Entry<String, Country> entry)->entry.getValue().getArea());

Using Collections.min

Collections.min(biggestCountries.entrySet(),comp);

Using stream

Entry<String, Country> entry = biggestCountries.entrySet()
                                               .stream()
                                               .min(comp)
                                               .orElse(null);

If you want to get only the Country, using stream

Country minCountry = biggestCountries.values()
                        .stream()
                        .min(Comparator.comparing(Country::getArea))
                        .orElse(null);

or using Collections.min

Country minCountry = Collections.min(biggestCountries.values(),
                           Comparator.comparing(Country::getArea));

Get key with minimum value

You can get the key and value using Object.entries:

var arr = {  lst1: 300,  lst2: 381,  lst3: 4,  lst4: 4,  lst5: 49};
function lowestValueAndKey(obj) {  var [lowestItems] = Object.entries(obj).sort(([ ,v1], [ ,v2]) => v1 - v2);  return `Lowest value is ${lowestItems[1]}, with a key of ${lowestItems[0]}`;}
var lowest = lowestValueAndKey(arr);console.log(lowest);

Find minimum key in map with Java 8 stream

Do you really need Map.Entry.comparingByValue()?

You can "implement" your (almost :)) own Comparator:

.min( (x, y) -> Long.compare(x.getValue().get(), y.getValue().get()) )

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