不重复打印排序数组中相加和为给定值的所有二元组

双指针的应用

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class Main {
    public static void main(String[] args) throws IOException {
        BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
        String[] str = reader.readLine().split(" ");
        int n = Integer.parseInt(str[0]);
        int k = Integer.parseInt(str[1]);
        str = reader.readLine().split(" ");
        reader.close();
        int[] arr = parse(str,n);
        int i = 0,j = n - 1;
        while(i < j){
            if(arr[i] + arr[j] == k){
                if(i==0 || arr[i] != arr[i - 1])
                System.out.println(arr[i] + " " + arr[j]);
                i++;
                j--;
            } else if(arr[i] + arr[j] > k) j--;
            else i++;
        }
    }
    private static int[] parse(String[] str,int n){
        int[] arr = new int[n];
        for(int i = 0;i < n;i++){
            arr[i] = Integer.parseInt(str[i]);
        }
        return arr;
    }
}