Solutionn with: two for loops, function which check the date and can throw ParseExcepion if something isn't right, StringBuilder contained solution and dataFormat.

src/main/java/core/basesyntax/SalaryInfo.java

@@ -1,7 +1,41 @@
 package core.basesyntax;
 
+import java.time.LocalDate;
+import java.time.format.DateTimeFormatter;
+
 public class SalaryInfo {
     public String getSalaryInfo(String[] names, String[] data, String dateFrom, String dateTo) {
-        return null;
+        StringBuilder result = new StringBuilder();
+        result.append("Report for period ").append(dateFrom).append(" - ").append(dateTo);
+
+        for (String name : names) {
+            int salary = 0;
+            String regexSymbol = " ";
+            for (String datum : data) {
+                String[] parts = datum.split(regexSymbol);
+                int dateIndex = 0;
+                int nameIndex = 1;
+                int hoursIndex = 2;
+                int incomeIndex = 3;
+                int hours = Integer.parseInt(parts[hoursIndex]);
+                int income = Integer.parseInt(parts[incomeIndex]);
+                if (parts[nameIndex].equals(name)
+                        && dateComparator(parts[dateIndex], dateFrom, dateTo)) {
+                    salary += hours * income;
+                }
+            }
+            result.append(System.lineSeparator()).append(name).append(" - ").append(salary);
+        }
+
+        return result.toString();
+    }
+
+    private static final boolean dateComparator(String data, String dataFrom, String dataTo) {
+        DateTimeFormatter format = DateTimeFormatter.ofPattern(("dd.MM.yyyy"));
+        LocalDate date = LocalDate.parse(data, format);
+        LocalDate dateFrom = LocalDate.parse(dataFrom, format);
+        LocalDate dateTo = LocalDate.parse(dataTo, format);
+        return !date.isBefore(dateFrom) && !date.isAfter(dateTo);
+
     }
 }