diff --git a/bin/StringCalculator.class b/bin/StringCalculator.class
index a937b0c..22ac1a3 100644
Binary files a/bin/StringCalculator.class and b/bin/StringCalculator.class differ
diff --git a/bin/StringCalculatorTest.class b/bin/StringCalculatorTest.class
index d44b83f..6b49710 100644
Binary files a/bin/StringCalculatorTest.class and b/bin/StringCalculatorTest.class differ
diff --git a/src/StringCalculator.java b/src/StringCalculator.java
index 487916b..a8e47cb 100644
--- a/src/StringCalculator.java
+++ b/src/StringCalculator.java
@@ -1,9 +1,123 @@
+import java.util.StringTokenizer;
 
 public class StringCalculator {
+	
+
+	public int getnumber(String nb1) {
+		
+		int i1 = Integer.parseInt(nb1);
+		return i1;
+		
+		}
+
+	public StringTokenizer decoupe (String nb) {
+		String delim = ",";
+		StringTokenizer s = new StringTokenizer(nb, delim);
+		return s;
+	}
+	public StringTokenizer decoupevirg (String nb) {
+		String delim = "/n";
+		StringTokenizer s = new StringTokenizer(nb, delim);
+		return s;
+		
+	}
+	public StringTokenizer decoupeeception1 (String nb) {
+		boolean Value=true;
+		String delim = ",/n";
+		StringTokenizer s = new StringTokenizer(nb, delim,Value);
+		return s;
+		
+	}
+	public StringTokenizer decoupeeception2 (String nb) {
+		boolean Value=true;
+		String delim = "/n,";
+		StringTokenizer s = new StringTokenizer(nb, delim, Value);
+		return s;
+		
+	}
+	public String identification(StringTokenizer s1) {
+		String n1 = s1.nextToken();
+		return n1;
+	}
 	public int add(String numbersStr) {
-		// Returns the sum of the numbers given in numbersStr
+		StringTokenizer s = decoupe(numbersStr);
+		int tokennb= s.countTokens();
+		String n1="0";
+		String n2="0";
+		if (tokennb==0){
+			n1="0";
+			n2="0";
+			}
+		if (tokennb==1){
+			n1=identification(s);
+			n2="0";
+			}
+		if (tokennb==2){
+			n1=identification(s);
+			n2=identification(s);
+		}
+		int sum = getnumber(n1) + getnumber(n2);
+		return sum;
+	}
+	public int add2(String numbersStr) {
+		StringTokenizer s = decoupe(numbersStr);
+		int tokennb= s.countTokens();
+		int sum=0;
+		if (tokennb==0) {
+			sum = 0;
+		}
+		else {
+		for (int i=1;i<=tokennb;i++) {
+			int num = getnumber(identification(s));
+			sum = sum +num;
+		}
+		
+		}
+		return sum;
+	}
+	public int add3(String numbersStr) {
+		StringTokenizer s1 = decoupeeception1(numbersStr);
+		StringTokenizer s2 = decoupeeception2(numbersStr);
+		int tokennb1= s1.countTokens();
+		int tokennb2= s2.countTokens();
+		boolean OK=true;
+		String n1="0";
+		String n2="0";
+		for (int i=1;i<=tokennb1;i++) {
+		n1 = identification(s1);
+		if (n1==",/n"){
+			OK= false;
+		}	
+		}
+		for (int i=1;i<=tokennb2;i++) {
+			n2 = identification(s2);
+		if (n2=="/n,") {
+			OK=false;
+		}
+		}
+		if (OK=true) {
+		StringTokenizer s = decoupe(numbersStr);
+		int tokennb= s.countTokens();
+		int sum=0;
+		if (tokennb==0) {
+			sum = 0;
+		}
+		else {
+		for (int i=1;i<=tokennb;i++) {
+			StringTokenizer s3= decoupevirg(identification(s));
+			int tokennb3= s3.countTokens();
+			for (int j=1;j<=tokennb3;j++) {
+			int num = getnumber(identification(s3));
+			sum = sum +num;
+			}
+		}
+		}
+		return sum;
+		}
+		else {
+			return 0;
+		}
 		
-		// not yet implemented
-		return 0;
 	}
+
 }
diff --git a/tests/StringCalculatorTest.java b/tests/StringCalculatorTest.java
index 4ec9afe..bdec86d 100644
--- a/tests/StringCalculatorTest.java
+++ b/tests/StringCalculatorTest.java
@@ -5,8 +5,38 @@
 public class StringCalculatorTest {
 
 	@Test
-	public void test() {
-		fail("Not yet implemented");
+	public void task1_2_number() {
+		StringCalculator sc = new StringCalculator();
+		assertEquals(3, sc.add("1,2"));
+	}
+	@Test
+	public void task1_0() {
+		StringCalculator sc = new StringCalculator();
+		assertEquals(0, sc.add(""));
+	}
+	@Test
+	public void task1_1_number() {
+		StringCalculator sc = new StringCalculator();
+		assertEquals(1, sc.add("1"));
+	}
+	@Test
+	public void add2_task1_multiple_number() {
+		StringCalculator sc = new StringCalculator();
+		assertEquals(30, sc.add2("1,8,3,9,4,3,2"));
+	}
+	@Test
+	public void add2_task1_multiple_number_0() {
+		StringCalculator sc = new StringCalculator();
+		assertEquals(0, sc.add2(""));
+	}
+	@Test
+	public void add3_task1_multiple_number() {
+		StringCalculator sc = new StringCalculator();
+		assertEquals(31, sc.add3("1,8,4/n9,4,3,2"));
+	}
+	@Test
+	public void add3_task1_multiple_number_virgn() {
+		StringCalculator sc = new StringCalculator();
+		assertEquals(13, sc.add3("1,8,4,/n"));
 	}
-
 }