Search a 2D Matrix II
Desicription
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.
Example:
Consider the following matrix:
1 2 3 4 5 6 7
 [ [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] ]

Given target = 5
, return true
.
Given target = 20
, return false
.
Solution
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
 class Solution { public: bool searchMatrix(vector<vector<int>>& matrix, int target) { int row = matrix.size(); if(row == 0) { return false; } int col = matrix[0].size(); if(col == 0) { return false; } int currentRow = 0; int currentCol = col  1; while(true) { if(currentRow >= row  currentCol < 0) { return false; } auto current = matrix[currentRow][currentCol]; if(target == current) { return true; } else if(target < current) { currentCol; } else if(target > current) { currentRow++; } } return false; } };
