import java.util.ArrayList;

import java.util.HashMap;

import java.util.List;

import java.util.Map;

public class DatasetMerger {

/**

* Merges multiple datasets of form fields into a single dataset.

*

* @param datasets A list of datasets, where each dataset is a map of field names to values.

* @return A merged dataset, which is a map of field names to values. Returns an empty map if input is null or empty.

*/

public static Map<String, String> mergeDatasets(List<Map<String, String>> datasets) {

// Handle null or empty input

if (datasets == null || datasets.isEmpty()) {

return new HashMap<>(); // Return an empty map if no datasets are provided.

}

// Initialize the merged dataset

Map<String, String> mergedDataset = new HashMap<>();

// Iterate through each dataset

for (Map<String, String> dataset : datasets) {

// Iterate through each field in the current dataset

for (Map.Entry<String, String> entry : dataset.entrySet()) {

String fieldName = entry.getKey();

String fieldValue = entry.getValue();

// Update the merged dataset. If the field already exists, overwrite the value.

mergedDataset.put(fieldName, fieldValue);

}

}

return mergedDataset;

}

public static void main(String[] args) {

// Example Usage

Map<String, String> dataset1 = new HashMap<>();

dataset1.put("name", "Alice");

dataset1.put("age", "30");

Map<String, String> dataset2 = new HashMap<>();

dataset2.put("city", "New York");

dataset2.put("occupation", "Engineer");

Map<String, String> dataset3 = new HashMap<>();

dataset3.put("name", "Bob");

dataset3.put("country", "USA");

List<Map<String, String>> datasets = new ArrayList<>();

datasets.add(dataset1);

datasets.add(dataset2);

datasets.add(dataset3);

Map<String, String> merged = mergeDatasets(datasets);

// Print the merged dataset

System.out.println(merged); // Expected output: {name=Bob, age=30, city=New York, occupation=Engineer, country=USA}

}

}