From 28b23aef754e6bae8427edc58a385ff49da24e0f Mon Sep 17 00:00:00 2001
From: Simranb10 <simranbhoir1096@gmail.com>
Date: Sun, 31 May 2026 23:42:24 -0400
Subject: [PATCH] Array-1 solution

---
 DiagonalTraverse.java  | 45 +++++++++++++++++++++++++++++++++++
 ProductExceptSelf.java | 24 +++++++++++++++++++
 SpiralOrder.java       | 53 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 122 insertions(+)
 create mode 100644 DiagonalTraverse.java
 create mode 100644 ProductExceptSelf.java
 create mode 100644 SpiralOrder.java

diff --git a/DiagonalTraverse.java b/DiagonalTraverse.java
new file mode 100644
index 00000000..3e1e549e
--- /dev/null
+++ b/DiagonalTraverse.java
@@ -0,0 +1,45 @@
+//Time Complexity: O(m*n)
+//Space Complexity: O(1)
+
+public class DiagonalTraverse {
+    public int[] findDiagonalOrder(int[][] mat) {
+        int m = mat.length;
+        int n = mat[0].length;
+        int[] result = new int[m * n];
+
+        int row = 0;
+        int col = 0;
+
+        boolean dir = true;
+
+        for (int index = 0; index < m * n; index++) {
+            result[index] = mat[row][col];
+            if (dir) {
+                if (col == n - 1) {
+                    row++;
+                    dir = false;
+                } else if (row == 0) {
+                    col++;
+                    dir = false;
+                } else {
+                    row--;
+                    col++;
+
+                }
+            } else {
+                if (row == m - 1) {
+                    col++;
+                    dir = true;
+
+                } else if (col == 0) {
+                    row++;
+                    dir = true;
+                } else {
+                    row++;
+                    col--;
+                }
+            }
+        }
+        return result;
+    }
+}
diff --git a/ProductExceptSelf.java b/ProductExceptSelf.java
new file mode 100644
index 00000000..f9e9a985
--- /dev/null
+++ b/ProductExceptSelf.java
@@ -0,0 +1,24 @@
+//Time Complexity: O(n)
+//Space Complexity: O(1)
+
+public class ProductExceptSelf {
+    int[] result;
+
+    public int[] productExceptSelf(int[] nums) {
+        int n = nums.length;
+        result = new int[n];
+        result[0] = 1;
+
+        for (int i = 1; i < n; i++) {
+            result[i] = nums[i - 1] * result[i - 1];
+        }
+
+        int product = 1;
+        for (int i = n - 2; i >= 0; i--) {
+            product = product * nums[i + 1];
+            result[i] = product * result[i];
+
+        }
+        return result;
+    }
+}
diff --git a/SpiralOrder.java b/SpiralOrder.java
new file mode 100644
index 00000000..0788572d
--- /dev/null
+++ b/SpiralOrder.java
@@ -0,0 +1,53 @@
+//Time Complexity : O(m*n)
+//Space Complexity : O(m+n)
+
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class SpiralOrder {
+    public List<Integer> spiralOrder(int[][] matrix) {
+        List<Integer> li = new ArrayList<>();
+
+        // Directrions
+        int top = 0;
+        int left = 0;
+        int bottom = matrix.length-1;
+        int right = matrix[0].length-1;
+
+        helper(matrix,top,bottom,left,right,li);
+        return li;
+    }
+
+    private void helper(int[][] matrix, int top, int bottom, int left, int right, List<Integer> li) {
+        //base case : while loop condition
+        if(left > right || top > bottom) return;
+
+        for (int i=left; i <= right; i++) {
+            li.add(matrix[top][i]);
+        }
+        top++;
+        //top to bottom
+        if(top <= bottom) {
+            for (int i=top; i <= bottom; i++) {
+                li.add(matrix[i][right]);
+            }
+        }
+        right--;
+        //right to left
+        if(top <= bottom) {
+            for (int i=right; i >= left; i--) {
+                li.add(matrix[bottom][i]);
+            }
+        }
+        bottom--;
+        //bottom to top
+        if(left <= right) {
+            for (int i=bottom; i >= top; i--) {
+                li.add(matrix[i][left]);
+            }
+        }
+        left++;
+        helper(matrix,top,bottom,left,right,li);
+    }
+}