what is the difference between these initializations?
Char a[]=”string”;
Char *p=”literal”;
Does *p++ increment p, or what it points to?
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Answer Posted / koti
Actually char a[ ]="string" in this scenario string constant is stored in read-only memory section and also stack section.in this case you can modify the string constant.that modifications are happened in stack section .so here
*a ++ men's
1 ) a is pointing to base address of string constant .
2 ) *a men's inside content that is 's'.
3 ) *a ++ men's incrementing the asci value of 's'. After that you can print this array like
Printf("%s",a);
O/P : ttring.
Coming to the *p ="literal" this scenario
1 ) *p is stored in stack section why because it is auto variable.
2 ) "literal" this string constant is stored in read-only memory section.
3 ) P is pointing to string constant Base addres
Here *p++ men's you are training to change read only memory section contact. so it is an error why because
You can't modified the read-only memory content.
Main difference is using arrays string constant is stored in both stack and read-only memory section.
Using pointers string constant is stored in read-only memory section only .
Thank you.
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Step by Step Implementation 1.Define two symbolic constants, one to hold the total volume of the disk (e.g. VOLUME) and another one to hold the number of entries the files system of the device can handle (MAXFOLD). 2.Define a new structure data type named DATE to store a date consisting of year, month and day as unsigned values. 3.Define an other structure data type FOLDER to store the information of one folder of photos: ◦A title as character array of appropriate length ◦The location (event) the photos are taken as character array of appropriate length ◦The date of the day the photos are copied to the disk using the just defined data type DATE ◦The number of photos as natural number ◦And the size of the folder in MB as floating point value 4.Define the following global variables and initialise them: ◦disk as an array with MAXFOLD elements of data type FOLDER ◦folders as natural value to count the number of folders currently stored at the disk (valid elements in the array) TEST: Now you should be able to compile the code the first time without any warning or error. 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