.idea/vcs.xml

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
   <component name="VcsDirectoryMappings">
-    <mapping directory="$PROJECT_DIR$" vcs="Git" />
+    <mapping directory="" vcs="Git" />
   </component>
 </project>

src/main/java/MainExercises.java

@@ -1,3 +1,6 @@
+import java.util.ArrayList;
+import java.util.List;
+
 public class MainExercises
 {
     /*
@@ -20,8 +23,21 @@ public class MainExercises
  */
     public char[][] generateTriangle(int n) {
 
-        // todo
-        return null;
+        char[][] triangle =  new char[n][];
+
+        for(int i = 0 ; i < n ; i++){
+            triangle[i] = new char[i+1];
+            for(int j = 0 ; j < i+1 ; j++){
+                if(i == 0 || j == 0 || i== j || i == n-1 ){
+                    triangle[i][j] = '*';
+                }
+                else{
+                    triangle[i][j] = ' ';
+                }
+            }
+        }
+
+        return triangle;
 
     }
 
@@ -57,11 +73,56 @@ public class MainExercises
            - Number of rows:    matrix.length
            - Number of columns: matrix[0].length (if rectangular)
    */
+
+
     public int[] spiralTraversal(int[][] matrix) {
-        // todo
-        return null;
+        int rows = matrix.length;
+        int columns = matrix[0].length;
+        int[] result = new int[rows*columns];
+
+        int top = 0;
+        int down = rows-1;
+        int left = 0;
+        int right = columns-1;
+        int counter = 0;
+
+        while(top <= down && left <= right){
+            for (int i = left ; i <= right ; i++){
+                result[counter] = matrix[top][i];
+                counter++;
+            }
+            top++;
+
+            for(int i = top ; i <= down ; i++){
+                result[counter] = matrix[i][right];
+                counter++;
+            }
+            right--;
+
+            if (counter < rows*columns){
+                for(int i = right ; i >= left ; i--){
+                    result[counter] = matrix[down][i];
+                    counter++;
+                }
+                down--;
+
+                for(int i = down ; i >= top ; i--){
+                    result[counter]= matrix[i][left];
+                    counter++;
+                }
+                left++;
+
+
+            }
+
+        }
+
+
+
+        return result;
     }
 
+
     /*
         integer partitioning is a combinatorics problem in discreet maths
         the problem is to generate sum numbers which their summation is the input number
@@ -90,11 +151,67 @@ public class MainExercises
         body to use them instead of arrays.
     */
 
+    private static  List<List<Integer>> result;
+    private static  List<Integer> help;
+
+
     public int[][] intPartitions(int n) {
-        // todo
-        return null;
+        result = new ArrayList<>();
+        help = new ArrayList<>();
+
+        findRecursive(n, n);
+
+        int[][] answer = casting(result);
+
+        return answer;
     }
 
+    private static void findRecursive(int target , int max){
+
+        if(target == 0){
+
+            result.add(new ArrayList<>(help));
+            return;
+        }
+
+        for(int i = Math.min(target , max) ; i >= 1 ; i--){
+            help.add(i);
+
+
+            findRecursive(target -i , i);
+
+            help.remove(help.size() -1);
+
+        }
+
+    }
+
+    private  int[][]  casting(List<List<Integer>> input){
+       int n = input.size();
+
+        int[][] answer = new int[n][];
+
+        for(int i = 0 ; i < n ; i++){
+            int k = input.get(i).size();
+            answer[i] =  new int[k];
+
+            for(int j = 0 ; j < k ; j++){
+                answer[i][j] = input.get(i).get(j);
+            }
+
+
+        }
+
+        return answer;
+
+
+
+    }
+
+
+
+
+
 
     public static void main()
     {