Two-dimensional array in java

Two-dimensional array in java

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  Experts Of Programming Created By:Anonymous
• 2.
  What is 2-DArray? • Array of Arrays. • 2-D array usually represented with rows and columns
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  2-D Array Declaration •We can declare 2-D array in following ways type[][] referencevariable; or type referencevariable[][]; For example: int marks[][]; Each element in the 2-D Array must be the same type.
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  Creation of 2-DArray arrayreferencevariable = new type[value][value]; For example : marks = new int[3][4];
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  More on 2-DArray Creation marks = new int[][] // incorrect; marks= new int[][4] // incorrect; marks = new int[3][] // correct;
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  2-D array inform of rows and columns: marks=new int[3][4];
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  Initialization of 2-DArray • After array creation we can initialize the 2-D array like this : • Arrayvariable[row][column]= value; • For example lets initialize the marks array :
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  marks[0][0]=8; marks[0][1]=9; marks[0][2]=10;marks[0][3]=7; 8 9 10 7Row 0 Col 0 Col 1 Col 3 Col 4 12 21 30 7 31 45 10 40 Row 1 Row 2 Col 0 Col 1 Col 2 Col 3 Col 0 Col 1 Col 2 Col 3 marks[1][0]=12; marks[1][1]=21; marks[1][2]=30; marks[1][3]=7; marks[2][0]=31; marks[2][1]=45; marks[2][2]=10; marks[2][3]=40;
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  8 9 107 12 21 30 7 31 45 10 40 Col 0 Col 2 Col 3Col 1 Row 0 Row 1 Row 2 Now if you want to access any element from 2-D array System.Out.Println(marks[1][2]); output = 30 System.Out.Println(marks[0][0]); output = 8
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  We can alsoinitialize the array at the time of array creation int[][] marks = new int{ {1,2,0,5}, {4,5,1,4}, {7,6,5,9} }
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  How we canget array length marks.length // tell us rows. marks[0].length // tell us columns.
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