Question

How to define, initialize and print 2D array (matrix) in JavaScript

Answer 1

var arr = [
  [11, 32, 13, 23],
  [20, 80, 990, 837],
  [83, 23, 832, 8392]
];
  
for (i = 0; i < 3; i++) {
    for (j = 0; j < 4; j++)
        document.write(arr[i][j] + "  ");
    document.write("<br/ >\n");
}


/*
run:
  
11 32 13 23
20 80 990 837
83 23 832 8392 
   
*/

 

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Answer 2

var arr = [];

arr.push([1,2]);
arr.push([3,4]);
arr.push([5,6]);

for (i = 0; i < 3; i++) {
    for (j = 0; j < 2; j++)
        document.write(arr[i][j] + " ");
    document.write("<br/ >\n");
}



/*
run:
 
1 2
3 4
5 6
    
*/

 

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Answer 3

var arr = [
  [11, 32, 13, 23, 1],
  [20, 80, 90, 87, 4],
  [83, 23, 32, 99, 8]
];
  
for (i = 0; i < arr.length; i++) {
    for (j = 0; j < arr[0].length; j++)
        document.write(arr[i][j] + "  ");
    document.write("<br/ >\n");
}


/*
run:
  
11 32 13 23 1
20 80 90 87 4
83 23 32 99 8 
   
*/

 

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