如何比较 2 个不同大小的二维数组？

Question

The first 2D array is

[[1, 10], [0, 4], [1, 1]]

The second 2D array is

[[0, 1], [0, 2], [0, 3], [0, 4], [0, 5], [0, 6], [0, 7], [0, 8], [0, 9], [0, 10]]

How do I find if they have values overlapping in the 2nd column?
And after finding the overlap, how do I replace the element in the 2nd 2D array with the 1st 2D array?

For example:
[1, 10] from the 1st 2D array has the same 2nd column value as [0, 10] from the 2nd 2D array. Then, I replace [0, 10] with [1, 10] .

Answer 1

    int[][] first = {{1, 10}, {0, 4}, {1, 1}};
    int[][] second = {{0, 1}, {0, 2}, {0, 3}, {0, 4}, {0, 5}, {0, 6}, {0, 7}, {0, 8}, {0, 9}, {0, 10}};

    // first lets build a map for easy lookup of values 
    // produces map {1=1, 4=0, 10=1}
    final Map<Integer, Integer> map = Stream.of(first)
            .collect(Collectors.toMap(key -> key[1], value -> value[0]));

    // then we can do simple loop
    for (int[] pair : second) {
        // and if it contains the key (second column)
        if (map.containsKey(pair[1])) {
            // then we can just replace the value
            pair[0] = map.get(pair[1]);
        }
    }

Answer 2

public static void main(String args[]) {
  int arr1[][] = {{1, 10}, {0, 4}, {1, 1}};
  for (int i = 0; i < arr1.length; i++)
  {
    int temp = arr1[i][1];
    if (temp > 0 && temp <= 10)
    {
      arr1[i][0] = 0;
    }
  }
}

Answer 3

If duplicate key found in first 2D array, the last one will override the previous value. Simple for loop for the beginner of Java.

public static void main(String[] args) {
    int[][] firsts = {{1, 10}, {0, 4}, {1, 1}};
    int[][] seconds = {{0, 1}, {0, 2}, {0, 3}, {0, 4}, {0, 5}, {0, 6}, {0, 7}, {0, 8}, {0, 9}, {0, 10}};

    for(int[] secondRow : seconds) {
        for(int[] firstRow: firsts) {
            if(firstRow[1] == secondRow[1])
                secondRow[0] = firstRow[0];
        }
    }       

    // Use for displaying updated result only
    for(int[] secondRow : seconds)
        System.out.println("[" + secondRow[0] + ", " + secondRow[1] + "]");     

}