Cpp pointers

Memory is a two column table. First row contains addresses, second row contains values.

int x = 4;

When variable is assigned, an empty memory row cell is chosen. Variable’s value is written to second column of the row.

Pointer

int* pX = &x;

Variable declaration with a * after type states that it is a pointer to that type. In this case, pX is an integer pointer. Instead of storing value, pointer variable store memory address in their value column (second column of a memory row).

& is for extracting address from a variable. &x means address of variable named x

Dereference

int y = *pX;

Variable with a preceding asterisk (*) referred to as a dereference. When used before a pointer variable, this expression will return a value in a row, to which such variable points to.

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