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Computer Science IGCSEPDF 120
142 pagesrevision 46930
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Now what if each student takes more than one subject? Well instead of making a 1D
array for each subject, we can use 2D arrays.
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DECLARE StudentMarks : ARRAY[1:20, 1:10] OF INTEGER
FOR StudentNo ← 1 TO 20
FOR SubjectNo ← 1 TO 10
OUTPUT "Enter marks of student no. ", StudentNo
OUTPUT "For subject no. ", SubjectNo
INPUT StudentMarks[StudentNo, SubjectNo]
NEXT SubjectNo
NEXT StudentNo
Main points
● Arrays are used to store a collection of values, instead of making too many
variables
● 1D arrays store values one by one, for a limited length
● 2D arrays are more like a table/grid, having rows and columns of where values
can be inserted into
8.2.3 Writing and Reading
Writing values
● Using INPUT
○ INPUT ArrayName[Index] for 1D
○ INPUT ArrayName[Row, Column] for 2D
● Using assignment
○ ArrayName[Index] ← Expression for 1D
○ ArrayName[Row, Column] ← Expression for 2D
Reading values
You can reference the array by
● ArrayName[Index] for 1D
● ArrayName[Row, Column] for 2D
Treat it like a normal variable.
8.3 File Handling