From 2c571ca96f4f184dca7a80612aca46d952695d1b Mon Sep 17 00:00:00 2001
From: chayan das <dasshuvo817@gmail.com>
Date: Fri, 14 Nov 2025 21:29:14 +0530
Subject: [PATCH] Create 2536. Increment Submatrices by One

---
 2536. Increment Submatrices by One | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)
 create mode 100644 2536. Increment Submatrices by One

diff --git a/2536. Increment Submatrices by One b/2536. Increment Submatrices by One
new file mode 100644
index 0000000..4ef904e
--- /dev/null
+++ b/2536. Increment Submatrices by One	
@@ -0,0 +1,28 @@
+class Solution {
+public:
+    vector<vector<int>> rangeAddQueries(int n, vector<vector<int>>& queries) {
+        vector<vector<int>> diff(n, vector<int>(n, 0));
+
+        // diff array updates
+        for (auto &q : queries) {
+            int row1 = q[0];
+            int col1 = q[1];
+            int row2 = q[2];
+            int col2 = q[3];
+
+            for (int i = row1; i <= row2; i++) {
+                diff[i][col1] += 1;
+                if (col2 + 1 < n) diff[i][col2 + 1] -= 1;
+            }
+        }
+
+        // prefix sum row-wise
+        for (int i = 0; i < n; i++) {
+            for (int j = 1; j < n; j++) {
+                diff[i][j] += diff[i][j - 1];
+            }
+        }
+
+        return diff;
+    }
+};