Is it possible to get the index of a 2D array? Suppose I have the following array
int[][] arr = {{41, 44, 51, 71, 63, 1}, {7, 88, 31, 95, 9, 6}, {88, 99, 6, 5, 77, 4}};
And I want to get the index of 88, how to do it?
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do you mean like search for an element and return its index/indices?Ahmad Y. Saleh– Ahmad Y. Saleh2012-03-04 12:56:27 +00:00Commented Mar 4, 2012 at 12:56
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4 Answers
for (int i = 0 ; i < size; i++)
for(int j = 0 ; j < size ; j++)
{
if ( arr[i][j] == 88)
{
`save this 2 indexes`
break;
}
}
Comments
If they are not sorted, you will have to loop through all indexes [using double loop] and check if it is a match.
int[][] arr = {{41, 44, 51, 71, 63, 1}, {7, 88, 31, 95, 9, 6}, {88, 99, 6, 5, 77, 4}};
for (int i = 0; i < arr.length; i++) {
for (int j = 0; j < arr[i].length; j++) {
if (arr[i][j] == 88) {
System.out.println("i=" + i + " j=" + j);
}
}
}
will result in:
i=1 j=1
i=2 j=0
Comments
This is a primitive array, so it should be directly accessibly with the index:
int[] indexValue = arr[88];
EDIT:
Sorry, reading it again, if you mean the indices of the item 88 then there are multiple occurrences of 88 so you would need to iterate through each index and look for a match in each, and also have the size of the arrays stored somewhere. If it's possible and doesn't impact on performance, use an ArrayList or Vector and store Integers objects instead.
1 Comment
amit
this is a 2d array,
arr[88] is a int[]. Also, it returns the element in index 88, and not the index of element 88 [which I think is what the OP is after]System.out.println(Arrays.toString(da(arr,88)));
}
static int[] da(int dt[][],int target){
for(int i=0;i<dt.length;i++){
for (int j = 0; j <dt[i].length ; j++) {
if(dt[i][j]==target){
return new int[]{i,j};
}
}
}
return new int[]{-1,-1};
}
}
