Is it possible to reduce the number of assignment operations in array exchange?-CodePudding

This method has a very simple behavior, as you can see. However, I was wondering if there's a way to simplify this code even further, since it's only doing assignment operations in order to exchange values from the array.

private Board exch(Board a, int i, int j) { // exchange two elements in the array
    int temp = a.board[i];
    a.board[j] = a.board[i];
    a.board[i] = temp;
    return a;
}

CodePudding user response：

In this particular case that you are using ints, there is a way to do this without using a temp variable, by using math expressions, but I wouldn't recommend it just because it makes the code less readable.

private Board exch(Board a, int i, int j) {
    a.board[i] = a.board[i]   a.board[j];
    a.board[j] = a.board[i] - a.board[j];
    a.board[i] = a.board[i] - a.board[j];
    return a;
}

Anyway, doing swaps the way you did is pretty common, so I am not sure why are you expecting to simplify even further

CodePudding user response：

Algorithmically there is no better way, but if you are just trying to save lines of coding you can always do this:

import java.util.Collections

//define your array

Collections.swap(arr, i, j);

after this arr will have the values swapped

CodePudding user response：

// exchange two elements in the array
private Board exch(Board a, int i, int j) { 
    
    a.board[i]=a.board[i] a.board[j];
    a.board[j]=a.board[i]-a.board[j];
    a.board[i]=a.board[i]-a.board[j];
    return a;

}