Search in 2D array of [sword finger Offer]

package com.codinginterviews; /** * Title: * Search in 2D array -- sword finger Offer 1 * * Title Description: * In a two-dimensional array (each one-dimensional array has the same length), each row is sorted in ascending order from left to right, * Each column is sorted in ascending order from top to bottom. * * Please complete a function, input such a two-dimensional array and an integer to determine whether the array contains the integer. * */ public class TwoDimensionalArrayLookup { /** * Train of thought: * 1,According to the characteristics of the array, search from the top right corner * 2,If equal, return true * 3,If the target value is greater than the current value, ignore the line and continue to search * 4,If the target value is less than the current value, ignore this column and continue searching */ public boolean find(int target, int [][] array) { if (array == null) { return false; } int rowNum = array.length; if (rowNum <= 0) { return false; } int colNum = array[0].length; if (colNum <= 0) { return false; } // Navigate to the top right element int i = 0; int j = rowNum - 1; // Current element int curVal; // ergodic while (i < rowNum && j >= 0) { curVal = array[i][j]; if (curVal == target) { return true; // Ignore this line and continue searching } else if (curVal < target) { i++; // Ignore this column to continue searching } else { j--; } } return false; } public static void main(String[] args) { int[][] array = {,,}; TwoDimensionalArrayLookup instance = new TwoDimensionalArrayLookup(); System.out.println(instance.find(1, array)); System.out.println(instance.find(5, array)); System.out.println(instance.find(9, array)); System.out.println(instance.find(4, array)); System.out.println(instance.find(10, array)); } }

10 November 2019, 11:24 | Views: 4594