Leetcode interview question 16.06: minimum difference

Title Description

Given two arrays of integers a and b, Calculate a pair of values with the absolute value of the minimum difference （ Take one value from each array ）, And return the difference of the logarithm

Example

Example 1：
Input ：{1, 3, 15, 11, 2}, {23, 127, 235, 19, 8}
Output ：3, That is, the value pair (11, 8)

The problem solving process

Ideas and steps

（1） Sort  +  Double pointer ;
（2）left  The pointer loops through the array  a,right  The pointer loops through the array  b, Record  diff  Is the difference between the data pointed to by the current two pointers ;
（3） If  diff > 0,right  The pointer increases by itself , If  diff < 0,left  The pointer increases by itself ;
（4） Each cycle compares the current  diff  The absolute value of and the final result  result  Size , Assign the small party to  result;
（5） It should be noted that  diff  Need to be defined as  long  Type of , Otherwise, the result will be wrong , such as  [-2147483648,1]  Numerical pair ,diff  by  -2147483649, If defined as  int  You'll cross the line .

Code display

public class SmallestDifference {
    

    public int smallestDifference(int[] a, int[] b) {
    
        Arrays.sort(a);
        Arrays.sort(b);
        int left = 0;
        int right = 0;
        int result = Integer.MAX_VALUE;
        while (left < a.length && right < b.length) {
    
            long diff = a[left] - b[right];
            long diffAbs = Math.abs(diff);
            result = (int)Math.min(diffAbs, result);
            if(diff > 0) {
    
                right++;
            } else {
    
                left++;
            }
        }
        return result;

    }

    public static void main(String[] args) {
    
        int[] a = {
    -2147483648,1};
        int[] b = {
    0,2147483647};
        System.out.println(new SmallestDifference().smallestDifference(a, b));
    }

}