LeetCode-in-All

240. Search a 2D Matrix II

Medium

Write an efficient algorithm that searches for a target value in an m x n integer matrix. The matrix has the following properties:

Example 1:

Input: 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]], target = 5

Output: true

Example 2:

Input: 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]], target = 20

Output: false

Constraints:

Solution

function searchMatrix(matrix: number[][], target: number): boolean {
    let r: number = 0
    let c: number = matrix[0].length - 1
    while (r < matrix.length && c >= 0) {
        if (matrix[r][c] === target) {
            return true
        } else if (matrix[r][c] > target) {
            c--
        } else {
            r++
        }
    }
    return false
}

export { searchMatrix }