program to create a map

void main(){
Map<String, String> countryCapital = {
  'USA': 'Washington, D.C.',
  'India': 'New Delhi',
  'China': 'Beijing'
};
  print(countryCapital);
}

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access a value in map using key

void main(){
Map<String, String> countryCapital = {
  'USA': 'Washington, D.C.',
  'India': 'New Delhi',
  'China': 'Beijing'
};
  print(countryCapital["USA"]);
}

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program to demonstrate properties of map

void main() {
 
  Map<String, double> expenses = {
    'sun': 3000.0,
    'mon': 3000.0,
    'tue': 3234.0,
  };
  
  print("All keys of Map: ${expenses.keys}");
  print("All values of Map: ${expenses.values}");
  print("Is Map empty: ${expenses.isEmpty}");
  print("Is Map not empty: ${expenses.isNotEmpty}");
  print("Length of map is: ${expenses.length}");
}

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program to add element to map

void main(){
Map<String, String> countryCapital = {
  'USA': 'Washington, D.C.',
  'India': 'New Delhi',
  'China': 'Beijing'
};
  // Adding New Item
  countryCapital['Japan'] = 'Tokio';
  print(countryCapital);
}

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program to update element in map

void main(){
Map<String, String> countryCapital = {
  'USA': 'Nothing',
  'India': 'New Delhi',
  'China': 'Beijing'
};
  // Updating Item
  countryCapital['USA'] = 'Washington, D.C.';
  print(countryCapital);
}

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convert keys and values in map to lists

void main() {
 
  Map<String, double> expenses = {
    'sun': 3000.0,
    'mon': 3000.0,
    'tue': 3234.0,
  };
  
  // Without List
  print("All keys of Map: ${expenses.keys}");
  print("All values of Map: ${expenses.values}");
 
  // With List
  print("All keys of Map with List: ${expenses.keys.toList()}");
  print("All values of Map with List: ${expenses.values.toList()}");
  
}

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program to demonstrate containsKey and containsValue function of map

void main() {
 
  Map<String, double> expenses = {
    'sun': 3000.0,
    'mon': 3000.0,
    'tue': 3234.0,
  };
  
  // For Keys
  print("Does Map contain key sun: ${expenses.containsKey("sun")}");
  print("Does Map contain key abc: ${expenses.containsKey("abc")}");
 
  // For Values
  print("Does Map contain value 3000.0: ${expenses.containsValue(3000.0)}");
  print("Does Map contain value 100.0: ${expenses.containsValue(100.0)}");
  
}

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program to remove item from map

void main(){
Map<String, String> countryCapital = {
  'USA': 'Nothing',
  'India': 'New Delhi',
  'China': 'Beijing'
};
  
  countryCapital.remove("USA");
  print(countryCapital);
}

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traverse values in map using for in Loop

void main(){

  Map<String, dynamic> book = {
    'title': 'Misson Mangal',
    'author': 'Kuber Singh',
    'page': 233
  };
  
 // Loop Through Map
  for(MapEntry book in book.entries){
    print('Key is ${book.key}, value ${book.value}');
  }
}

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traverse map using forEach Loop

void main(){

  Map<String, dynamic> book = {
    'title': 'Misson Mangal',
    'author': 'Kuber Singh',
    'page': 233
  };
  
  
 // Loop Through For Each
  book.forEach((key,value)=> print('Key is $key and value is $value'));
  
}

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program to demonstrate removewhere function to remove item from map based on a condition

void main() {
  Map<String, double> mathMarks = {
    "ram": 30,
    "mark": 32,
    "harry": 88,
    "raj": 69,
    "john": 15,
  };
  mathMarks.removeWhere((key, value) => value < 32);
  print(mathMarks);
}

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program to demonstrate removeWhere function of map that removes element from map based on a 
condition

void main() {
  Map<String, double> mathMarks = {
    "ram": 30,
    "mark": 32,
    "harry": 88,
    "raj": 69,
    "john": 15,
  };

  mathMarks.removeWhere((key, value) => value < 32);

  print(mathMarks);
}
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