Create naren.java

Author: narendasan

Strings/Fraud Detection/naren.java

@@ -0,0 +1,144 @@
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.Hashtable;
+import java.util.TreeSet;
+import java.util.List;
+import java.util.ArrayList;
+import java.util.Iterator;
+
+
+public class Solution {
+
+    public static Hashtable<String, List<Record>> fraudsEmail = new Hashtable<String, List<Record>>();
+    public static Hashtable<String, List<Record>> fraudsAddr = new Hashtable<String, List<Record>>();
+    public static TreeSet<Integer> fraudsOrder = new TreeSet<Integer>();
+
+    public static class Address {
+        protected String streetAddr;
+        protected String city;
+        protected String state;
+        protected String zip;
+    }
+
+    public static class Record {
+        protected String orderID;
+        protected String dealID;
+        protected String email;
+        protected Address addr;
+        protected String card;
+    }
+
+    private static Record createRecord(String[] input) {
+        Address addr = new Address();
+        Record rec = new Record();
+        addr.streetAddr = input[3];
+        addr.city = input[4];
+        addr.state = input[5];
+        addr.zip = input[6];
+        rec.addr = addr;
+        rec.orderID = input[0];
+        rec.dealID = input[1];
+        rec.email = input[2];
+        rec.card = input[7];
+        return rec;
+    }
+
+    private static String parseEmailKey(String email) {
+        String [] emailInput = email.split("@");
+        String username = emailInput[0].toLowerCase();
+        String emailKey = username.contains("+") ? username.split("\\+")[0] : username;
+        emailKey = emailKey.replace(".", "");
+        return emailKey;
+    }
+
+   
+    private static void detectFraudEmail(Record rec) {
+        String emailKey = parseEmailKey(rec.email);
+        String fraudsEmailKey = emailKey + rec.dealID;
+        if ( fraudsEmail.containsKey(fraudsEmailKey) ) {
+            List<Record> recList = fraudsEmail.get(fraudsEmailKey);
+            for (Record r : recList) {
+                if ( !rec.card.equals(r.card) ) {
+                    fraudsOrder.add( Integer.parseInt(rec.orderID) );
+                    fraudsOrder.add( Integer.parseInt(r.orderID) );
+                }
+            }
+            recList.add( rec );
+        } else {
+            fraudsEmail.put( fraudsEmailKey, new ArrayList<Record> () );
+            fraudsEmail.get( fraudsEmailKey ).add( rec );
+        }
+    }
+
+    
+    private static String createAddrKey(Address addr) {
+        String stAddr = addr.streetAddr.toLowerCase();
+        String city = addr.city.toLowerCase();
+        String state = addr.state.toLowerCase();
+        String zip = addr.zip;
+        
+        int length = stAddr.length();
+        String lastTokenStAddr = stAddr.substring( length-3 );
+        if ( lastTokenStAddr.equals("st.") ) {
+            stAddr = stAddr.substring( 0, length-3 ) + "street";
+        } else if ( lastTokenStAddr.equals("rd.") ) {
+            stAddr = stAddr.substring( 0, length-3 ) + "road";
+        }
+
+        if ( state.equals("new york") ) {
+            state = "ny";
+        } else if ( state.equals("california") ) {
+            state = "ca";
+        } else if ( state.equals("illinois") ) {
+            state = "il";
+        }
+        return stAddr + city + state + zip;
+    }
+
+    /**
+    *   Function to detect frauds type: same address, same deal id, different
+    *   credit card.
+    */
+    private static void detectFraudAddr(Record rec) {
+        String addrKey = createAddrKey(rec.addr);
+        String fraudsAddrKey = addrKey + rec.dealID;
+        if ( fraudsAddr.containsKey(fraudsAddrKey) ) {
+            List<Record> recList = fraudsAddr.get( fraudsAddrKey );
+            for (Record r : recList) {
+                if ( !rec.card.equals(r.card) ) {
+                    fraudsOrder.add( Integer.parseInt(rec.orderID) );
+                    fraudsOrder.add( Integer.parseInt(r.orderID) );
+                }
+            }
+            recList.add( rec );
+        } else {
+            fraudsAddr.put( fraudsAddrKey, new ArrayList<Record> () );
+            fraudsAddr.get( fraudsAddrKey ).add( rec );
+        }
+    }
+
+
+      public static void main(String [] args) throws IOException {
+        BufferedReader in = new BufferedReader( new InputStreamReader ( System.in ) );
+        int testCase = Integer.parseInt( in.readLine() );
+        for (int i = 0; i < testCase; i++) {
+            String line = in.readLine();
+            String [] input = line.split(",");
+            Record rec = createRecord( input );
+            detectFraudEmail(rec);
+            detectFraudAddr(rec);
+        }
+        
+        String lineToPrint = "";
+        Iterator<Integer> iter = fraudsOrder.iterator();
+        while ( iter.hasNext() ) {
+            lineToPrint += iter.next() + ",";
+        }
+        if ( !lineToPrint.equals("") ) {
+            lineToPrint = lineToPrint.substring( 0, lineToPrint.length()-1);
+        }
+        System.out.println( lineToPrint );
+
+    }
+}