diff --git a/src/googleNaive.adb b/src/googleNaive.adb
index ed54559..ec07112 100644
--- a/src/googleNaive.adb
+++ b/src/googleNaive.adb
@@ -1,5 +1,108 @@
 package body googleNaive is
 
-    -- TODO
+    function "*"(left, right: T_Google) return T_Google is
+        M : T_Google;
+        n, m, o: Positive;
+        Compteur : Integer;
+    begin
+        n:=left.dimension(0);
+        m:=right.dimension(1);
+        o :=left.dimension(1);
+        initialize(M,n,m);
+        for i in 0..n loop
+            for j in 0..m loop
+                Compteur:=0;
+                for l in 0..o loop
+                    Compteur:= Compteur + left.matrix(i,l)*right.matrix(l,j);
+                end loop;
+                M.matrix(i,j):=Compteur;
+            end loop;
+        end loop;
+        return M;
+    end "*";
 
-end googleNaive;
\ No newline at end of file
+    function "+"(left, right: T_Google) return T_Google is
+        n, m : Positive;
+        M : T_Google;
+    begin
+        n := left.dimension(0);
+        m := left.dimension(1);
+        initialize(M,n,m);
+        for i in 0..n loop
+            for j in 0..m loop
+                M(i,j):=left.matrix(i,j) + right.matrix(i,j);
+            end loop;
+        end loop;
+        return M;
+    end "+";
+
+    function "*"(left: T_Google; right: Integer) return T_Google is
+        n, m : Positive;
+        M : T_Google;
+    begin
+        n := left.dimension(0);
+        m := left.dimension(1);
+        initialize(M,n,m);
+        for i in 0..n loop
+            for j in 0..m loop
+                M(i,j):=right*left.matrix(i,j);
+            end loop;
+        end loop;
+        return M;
+    end "*";
+
+    function "/"(left: T_Google; right: Integer) return T_Google is
+        n, m : Positive;
+        M : T_Google;
+    begin
+        n := left.dimension(0);
+        m := left.dimension(1);
+        initialize(M,n,m);
+        for i in 0..n loop
+            for j in 0..m loop
+                M(i,j):=left.matrix(i,j)/right;
+            end loop;
+        end loop;
+        return M;
+    end "/";
+
+    function zeros(rows, cols: in  Positive) return T_Google is
+        M : T_Google;
+    begin
+        initialize(M,rows,cols);
+        for i in 1..cows loop
+            for j in 1..cols loop
+                M(i,j):=0;
+            end loop;
+        end loop;
+    end zeros;
+
+    function ones(rows, cols: in  Positive) return T_Google is
+        M : T_Google;
+    begin
+        initialize(M,rows,cols);
+        for i in 1..cows loop
+            for j in 1..cols loop
+                M(i,j):=1;
+            end loop;
+        end loop;
+    end ones;
+
+    procedure insert(mat: in out T_Google; i, j: Natural; elm: T_Element) is
+    begin
+        mat.matrix(i,j):=elm;
+    end insert;
+
+    procedure initialize(mat: out T_Google; rows, cols : Positive ) is
+
+    begin
+        mat.dimension(0):=rows;
+        mat.dimension(1):=cols;
+    end initialize;
+
+
+
+
+
+
+end googleNaive;
diff --git a/src/googleNaive.ads b/src/googleNaive.ads
index 6aa8c9c..3b332e6 100644
--- a/src/googleNaive.ads
+++ b/src/googleNaive.ads
@@ -8,17 +8,22 @@ package googleNaive is
     type T_Row is limited private;
     type T_Google is limited private;
 
-    function "*"(left, right: T_Google) return T_Google;
-    function "+"(left, right: T_Google) return T_Google;
+    function "*"(left, right: T_Google) return T_Google with
+            Pre => left.dimension(1)=right.dimension(0),
+            Post => "*"'Result.dimension(0)= left.dimension(0) and "*"'Result.dimension(1)= right.dimension(1);
+
+    function "+"(left, right: T_Google) return T_Google with
+            Pre => left.dimension=right.dimension;
 
     function "*"(left: T_Google; right: Integer) return T_Google;
-    function "/"(left: T_Google; right: Integer) return T_Google;
+    function "/"(left: T_Google; right: Integer) return T_Google with
+            Pre => right/=0;
 
-    procedure initialize(mat: in out T_Google) with
+    procedure initialize(mat: out T_Google; rows, cols : Positive )with
         Post => isEmpty(mat);
 
-    function ones(rows, cols: Positive) return T_Google;
-    function zeros(rows, cols: Positive) return T_Google;
+    function ones(rows, cols: in Positive) return T_Google;
+    function zeros(rows, cols: in  Positive) return T_Google;
 
     procedure insert(mat: in out T_Google; i, j: Natural; elm: T_Element);
 
@@ -32,4 +37,4 @@ private
         matrix: array (0..CAPACITY-1) of T_Row;
     end record;
 
-end googleNaive;
\ No newline at end of file
+end googleNaive;