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2d address calculation

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2d address calculation

Dec 7th, 2005

plz give me links or discuss on address calculation in 2d arrays.
i have little knowledge of calculating the address. can any one give some formula or something coz my professor gave it but i wasnt able to follow . i remember he was using terms like rowmajor, column major, lower base , upper base etc.
so if any one is having knowledge plz help as this topic is not even in the book that i am using ( the course book i mean).

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Re: 2d address calculation

Dec 7th, 2005

See Address Calculation

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Re: 2d address calculation

Dec 7th, 2005

In C and C++, arrays are stored in memory by row. That is, all the columns of the first row appear first, then all the columns of the second row, etc. If you have an int array with 2 rows and 5 columns then the location of any given row can be caluculated by this formula

 Help with Code Tags 
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int *p = array + ((row_numer-1) * NumColumns)
int *p = array + ((row_numer-1) * NumColumns)

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
int array[2][5];
// set a pointer at the beginning of row 2
int* ptr = (int*)array + (1*5);
int array[2][5];
// set a pointer at the beginning of row 2
int* ptr = (int*)array + (1*5);