Array: a two-dimensional array to find

2019-09-13

Title Description

　　(The length of each one-dimensional array of same), each row from left to right in order of ascending sort, to sort each column in a two-dimensional array in order of increasing from top to bottom. A complete function, enter such a two-dimensional array and an integer, it is determined whether the array contains the integer.

Problem-solving ideas

 　　From the subject point of view, this two-dimensional arrays are ordered, from the top right to see, to the left decreasing, increasing downward.

1. 1. From the upper right arr [1] [j] starts looking for, if arr [1] [j]> N, then the left;
   2. If arr [1] [j] <N, then down;
   3. If it exceeds the boundary, then N is not in the two-dimensional array;

Reference Code

 1 public class Solution {
 2     public boolean Find(int target, int [][] array) {
 3         if(array.length == 0 || array[0].length == 0) {
 4             return false;
 5         }
 6         int m = array.length - 1;
 7         int n = 0;
 8         int temp = array[n][m];
 9         while(temp != target) {
10             if(m > 0 && n < array.length - 1) {
11                 if(temp < target) {
12                     n++;
13                 }
14                 if(temp > target) {
15                     m--;
16                 }
17                 temp = array[n][m];
18             }else {
19                 return false;
20             }
21         }
22         return true;
23     }
24 }