Day 65 leet code problem - Search a 2D matrix

Author: mandliya

README.md

@@ -169,4 +169,4 @@ Include contains single header implementation of data structures and some algori
 | Problem | Solution |
 | :------------ | :----------: |
 | Given a sorted integer array without duplicates, return the summary of its ranges. For example, given [0,1,2,4,5,7], return ["0->2","4->5","7"].| [summary_ranges.cpp](leet_code_problems/summary_ranges.cpp)|
- 
+| Given a 2D matrix, with following properties <ul><li>Integers in each row are sorted in ascending from left to right.</li></ul><ul><li>Integers in each column are sorted in ascending from top to bottom.</ul></li>|[search2DII.cpp](leet_code_problems/search2DII.cpp)|

leet_code_problems/search2DII.cpp

@@ -0,0 +1,43 @@
+/**
+ * Write an efficient algorithm that searches for a value in an m x n matrix. This matrix has the following properties:
+ * Integers in each row are sorted in ascending from left to right.
+ * Integers in each column are sorted in ascending from top to bottom.
+ */
+
+#include <iostream>
+#include <vector>
+
+bool searchMatrix( std::vector<std::vector<int>> matrix, int target ) {
+	int M = matrix.size();
+	int N = matrix[0].size();
+	if ( target < matrix[0][0] || target > matrix[M-1][N-1] ) {
+		return false;
+	}
+
+	int row = 0;
+	int col = N - 1;
+	while ( row <= M -1 && col >= 0 ) {
+		if ( matrix[row][col] == target ) {
+			return true;
+		} else if ( matrix[row][col] > target ) {
+			col--;
+		} else {
+			row++;
+		}
+	}
+	return false;
+}
+
+int main() {
+  std::vector<std::vector<int>> matrix = {
+    {1,   4,  7, 11, 15},
+    {2,   5,  8, 12, 19},
+    {3,   6,  9, 16, 22},
+    {10, 13, 14, 17, 24},
+    {18, 21, 23, 26, 30}
+  };
+  std::cout << searchMatrix(matrix, 5) << std::endl;
+  std::cout << searchMatrix(matrix, 20) << std::endl;
+  return 0;
+}
+