Notesale: Turn your study into money

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1
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This can be extended to both sides, making it open-ended
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Storing Values in Memory
To store a value in memory, we need to know how much space will be allocated for it
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The number 5
would need to be converted to binary, which is 32 bits or 4 bytes
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So, if we were
storing an integer, it would take up 2-4 bytes in memory
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For example, the value stored in a
variable could be 5, which would be represented as 101 in binary
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For example, an
array of characters would be of the data type char, and an array of integers would be of
the data type int
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To declare an array in programming, we use a specific syntax
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To declare an array, we would use:
int a[16];
This creates an array called "a" with 16 elements
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For example, we could initialize an array of
integers with the values 1, 2, and 3 like this:
int a[3] = {1, 2, 3};

Representing Arrays in Memory
To represent an array in memory, we need to know how the elements of the array are
stored
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Each element of the array takes up space in memory, depending on its data type
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Overall, understanding memory and arrays is crucial to programming, as they are
fundamental building blocks of many programs and applications
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All the elements in an
array are stored in consecutive/continuous locations with the index starting at zero
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One important point to note is that arrays are fixed-size
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Accessing Array Elements
The index of the array starts at zero (although it can start at one in some cases)
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To access an element, use the formula: base address + (i * size of data type)
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Dynamic Allocation
The drawback of arrays is that the size needs to be specified at compile time, which may
not always be possible
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If we
allocate more space than needed, there will be unused memory
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To dynamically allocate memory, we use functions such as 'malloc' and 'calloc'
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