DiagonalSum is added

pradeepkumar24rk · pradeepkumar24rk · commit 5c651e351960 · 2026-03-30T23:54:19.000+05:30
diff --git a/ArrayBasedProblems/DiagonalSum.java b/ArrayBasedProblems/DiagonalSum.java
@@ -0,0 +1,33 @@
+package ArrayBasedProblems;
+
+public class DiagonalSum {
+    public static void main(String[] args) {
+        int[][] matrix = { { 1, 2, 3 }, { 4, 5, 6 }, { 7, 8, 9 } };
+        System.out.println("Diagonal sum: " + diagonalSum(matrix));
+    }
+    
+    public static int diagonalSum(int[][] matrix) { // O(n) time and O(1) space
+        int sum = 0;
+        for (int i = 0; i < matrix.length; i++) {
+            sum += matrix[i][i];
+            if (i != matrix.length - i - 1) {
+                sum += matrix[i][matrix.length - i - 1];
+            }
+        }
+        return sum;
+    }
+    
+    public int bruceForce(int[][] mat) { // O(n^2) time and O(1) space
+        int sum = 0;
+        int col = mat[0].length-1;
+        for(int i =0;i<mat.length;i++) {
+            for(int j = 0;j<mat[0].length;j++) {
+                if(i==j || j==(col-i)){
+                    System.out.println(mat[i][j]);
+                    sum += mat[i][j];
+                }
+            }
+        }
+        return sum;
+    }
+}
